Louis Agassiz: His Life and Correspondence
by
Louis Agassiz
Part 8 out of 10
the greatest pleasure to have an opportunity of laying before you
some statements and reflections, which I trust may satisfy you that
geology and natural history can be made subservient to the great
interests of a civilized community, to a far greater extent than is
generally admitted.
The question of the harbor of Boston, for instance, has a
geological and zoological side, thus far only indirectly
considered. In order to ascertain whence the materials are derived
which accumulate in the harbor, the shores ought to be studied
geologically with a kind of accuracy and minuteness, never required
by geological surveys made for economical purposes. The banks of
the harbor, wherever it is not rock-bound, consist of drift, which
itself rests upon the various rock formations of the district. Now
this drift, as I have ascertained, formerly extended many miles
beyond our present shores, and is still slowly washed away by the
action of tides, winds, and currents. Until you know with precision
the mineralogical composition of the drift of the immediate
vicinity, so accurately indeed as to be able to recognize it in any
new combination into which it may be brought when carried off by
the sea, all your examination of soundings may be of little use.
Should it, however, be ascertained that the larger amount of loose
material spreading over the harbor is derived from some one or
other of the drift islands in the bay, the building of sea-walls to
stop the denudation may be of greater and more immediate use than
any other operation. Again, it is geologically certain that all the
drift islands of the harbor have been formed by the encroachment of
the sea upon a sheet of drift, which once extended in unbroken
continuity from Cape Ann to Cape Cod and farther south. This sheet
of drift is constantly diminishing, and in centuries to come,
which, notwithstanding the immeasurable duration of geological
periods, may be reached, I trust, while the United States still
remains a flourishing empire, it will be removed still further; so
far indeed, that I foresee the time when the whole peninsula of
Cape Cod shall disappear. Under these circumstances, it is the duty
of a wise administration to establish with precision the rate and
the extent of this destruction, that the coming generations may be
forewarned. In connection with this I would advise the making of a
thorough survey of the harbor, to ascertain the extent of rock
surface and of drift, and the relative position of the two, with
maps to show their relations to the different levels of the sea,
whereby the unequal action of the tides upon the various beaches
may be estimated.
The zoological side of the question relates to the amount of loose
materials accumulating in consequence of the increase of animal and
vegetable life, especially of those microscopic beings which,
notwithstanding their extraordinary minuteness, form in course of
time vast deposits of solid materials. Ehrenberg has shown that the
harbor of Wismar, on the Prussian coast of the Baltic, is filling,
not in consequence of the accumulation of inorganic sediments, but
by the rapid increase and decay of innumerable animalcules. To what
extent such deposits may accumulate has also been shown by
Ehrenberg, who ascertained, many years ago, that the city of Berlin
rests upon a deposit of about eighteen feet in thickness,
consisting almost exclusively of the solid parts of such
microscopic beings. These two cases may suffice to show how
important may be a zoological investigation of the harbor deposits.
I need hardly add that the deposits floated into the harbor, by the
numerous rivers and creeks which empty into it, ought to be
investigated with the same care and minuteness as the drift
materials. This investigation should also include the drainage of
the city.
But this is only a small part of the application I would recommend
to be made of geological and zoological knowledge, to the purposes
of the Coast Survey. The reefs of Florida are of the deepest
interest, and the mere geodetic and hydrographic surveys of their
whole range would be far from exhausting the subject. It is my
deliberate opinion that the great reefs of Florida should be
explored with as much minuteness and fullness as the Gulf Stream,
and that the investigation will require as much labor as has thus
far been bestowed on the Gulf Stream. Here again geological and
zoological knowledge is indispensable to the completion of the
work. The reef is formed mainly by the accumulation of solid
materials from a variety of animals and a few plants. The relations
of these animals and plants to one another while alive, in and upon
the reef, ought to be studied more fully than has been the case
heretofore, in order to determine with certainty the share they
have in the formation of these immense submarine walls so dangerous
to navigation. The surveys, as they have been made thus far,
furnish only the necessary information concerning the present form
and extent of the reef. But we know that it is constantly changing,
increasing, enlarging, spreading, rising in such a way and at such
a rate, that the surveys of one century become insufficient for the
next. A knowledge of these changes can only be obtained by a
naturalist, familiar with the structure and mode of growth of the
animals. The survey I made about fifteen years ago, at the request
of your lamented predecessor, could only be considered as a
reconnaissance, in view of the extent and importance of the work. I
would, therefore, recommend you to organize a party specially
detailed to carry on these investigations in connection with, and
by the side of, the regular geodetic and hydrographic survey. Here,
also, would geological knowledge be of great advantage to the
explorer. In confirmation of my recommendation I need only remind
you of a striking fact in the history of our science. More than
thirty years ago, before Dana and Darwin had published their
beautiful investigations upon the coral reefs, a pupil of mine, the
late Armand Gressly, had traced the structure and mode of growth of
coral reefs and atolls in the Jura mountains, thus anticipating, by
a geological investigation, results afterward obtained by dredging
in the ocean. The structure of the reefs of our shores is,
therefore, more likely to be fully understood by one who is
entirely familiar with zoology and geology than by a surveyor who
has no familiarity with either of these sciences.
There is another reason why I would urge upon you the application
of natural sciences to the work of the survey. The depth of the
ocean is a great obstacle to a satisfactory exploration of its
bottom. But we know now that nearly all dry land has been sea
bottom before it was raised above the level of the water. This is
at least the case with all the stratified rocks and aqueous
deposits forming part of the earth's crust. Now it would greatly
facilitate the study of the bottom of the sea if, after
ascertaining by soundings the general character of the bottom in
any particular region, corresponding bottoms on dry land were
examined, so that by a comparison of the one with the other, both
might be better understood. The shoals of the southern coast of
Massachusetts have been surveyed, and their position is now known
with great accuracy; but their internal structure, their mode of
formation, is only imperfectly ascertained, owing to the difficulty
of cutting into them and examining in situ the materials of which
they are composed. Nothing, on the contrary, is easier than to
explore the structure or composition of drift hills which are cut
through by all our railroad tracks. Now the shoals and rips of
Nantucket have their counterparts on the main-land; and even along
the shores of Boston Harbor, in the direction of Dorchester and
Milton, such shoals may be examined, far away from the waters to
which they owe their deposits. Here, then, is the place to complete
the exploration, for which soundings and dredgings give only
imperfect information.
I need not extend these remarks further in order to satisfy you of
the importance of geological and zoological researches in
connection with the regular operations of the Coast Survey. Permit
me, however, to add a few words upon some points which, as it seems
to me, belong legitimately to the Coast Survey, and to which
sufficient attention has not yet been paid. I allude, first, to the
salt marshes of our shores, their formation and uses, as well as
their gradual disappearance under the advance of the sea; second,
to the extended low islands in the form of reefs along the coast of
the Southern States, the bases of which may be old coral reefs;
third, the form of all our estuaries, which has resulted from the
conflict of the sea with the drift formation, and is therefore, in
a measure, a geological problem; fourth, the extensive deposits of
foraminifera along the coast, which ought to be compared with the
deposits of tripoli found in many tertiary formations; fifth, the
general form and outline of our continent, with all its
indentations, which are due to their geological structure. Indeed,
the shore everywhere is the result of the conflict of the ocean
with the rock formation of the land, and therefore as much a
question for geology as geodesy to answer.
Should the preceding remarks induce you to carry my suggestions
into practical operation, be assured that it will at all times give
me the greatest pleasure to contribute to the success of your
administration, not only by advice, but by actual participation in
your work whenever that is wanted. The scientific men of America
look to you for the publication of the great results already
secured by the Coast Survey, well knowing that this national
enterprise can only be benefited by the high-minded course which
has at all times marked your intellectual career.
Ever truly your friend,
L. AGASSIZ.
This year closed for Agassiz with a heavy sorrow. His mother's
health had been failing of late, and November brought the news of
her death. Separated though they were, there had never been any
break in their intercourse. As far as he could, he kept her advised
of all his projects and undertakings, and his work was no less
interesting to her when the ocean lay between them than when he
could daily share it with her. She had an unbounded sympathy with
him in the new ties he had formed in this country, and seemed
indeed as intimately allied with his later life here as with its
earlier European portion.
His own health, which had seemed for a time to have regained the
vigor of youth, broke down again in the following spring, and an
attack about the region of the heart disabled him for a number of
weeks. To this date belongs a short correspondence between Agassiz
and Oswald Heer. Heer's work on the Fossil Flora of the Arctics had
recently appeared, and a presentation copy from him reached Agassiz
as he was slowly regaining strength after his illness, although
still confined to the house. It could not have come at a happier
moment, for it engrossed him completely, and turned his thoughts
away from the occupations which he was not yet allowed to resume.
The book had a twofold interest for him: although in another branch
of science, it was akin to his own earlier investigations, inasmuch
as it reconstructed the once rich flora of the polar regions as he
himself had reconstructed the fauna of past geological times; it
clothed their frozen fields with forests as he had sheeted now
fertile lands with ice. In short, it appealed powerfully to the
imagination, and no child in the tedious hours of convalescence was
ever more beguiled by a story-book than he by the pictures which
this erudite work called up.
AGASSIZ TO OSWALD HEER.
CAMBRIDGE, May 12, 1868.
MY HONORED COLLEAGUE,
Your beautiful book on the Fossil Arctic Flora reached me, just as
I was recovering from a tedious and painful illness. I could,
therefore, take it in hand at once, and have been delighted with
it. You give a captivating picture of the successive changes which
the Arctic regions have undergone. No work could be more valuable,
either as a means of opening recent investigations in Paleontology
to the larger public, or of advancing science itself. If I can find
the time I mean to prepare an abridgment in popular form for one of
our reviews. Meantime I have written to Professor Henry,
Superintendent of the Smithsonian Institution at Washington, that
he should subscribe for a number of copies to be distributed among
less wealthy establishments. I hope he will do this, and I shall
continue to urge it, since my friendly relations with him give me a
right so to do. I have, moreover, written to the directors of
various prominent institutions, in order that your work, so far as
is possible for works of that kind, may become known in the United
States, and reach such persons as would naturally be interested in
it. . .
With friendly remembrance, yours always,
LOUIS AGASSIZ.
The answer is some months later in date, but is given here for its
connection.
FROM OSWALD HEER.
ZURICH, December 8, 1868.
MY HONORED FRIEND,
Your letter of last May gave me the greatest pleasure, and I should
have answered it earlier had I not heard that you had gone to the
Rocky Mountains, and supposed, therefore, that my letter would
hardly find you at home again before the late autumn. I will delay
writing no longer,--the more so because I have received, through
the Smithsonian Institution, your great work on the Natural History
of the United States. Valuable as it is in itself, it has a double
attraction for me as the gift of the author. Accept my warm thanks.
It will always be to me a token of your friendly regard. It gave me
great satisfaction to know that my Fossil Arctic Flora had met with
your approval. Since then many new facts have come to light tending
to confirm my results. The Whymper Expedition brought to England a
number of fossil plants, which have been sent to me for
examination. I found eighty species, of which thirty-two from North
Greenland are new, so that we now know 137 species of Miocene
plants from North Greenland (70 degrees north latitude). It was a
real delight to me to find the fruit cup of the Castanea [chestnut]
inclosing three seeds (three Kastanica) and covered with prickles
like the Castanea vesca; and, furthermore, I was able to prove by
the flowers, which were preserved with the fruit, that the
supposition given in the Arctic Flora (page 106) was correct;
namely, that the leaves of the Fagus castaneafolia Ung. truly
belong to a Castanea. As several fruits are contained in one fruit
cup, this Miocene Castanea must have been nearer to the European
species (C. vesca) than to the American Castanea (the C. pumila
Micha). The leaves have been drawn in the Flora Arctica, and are
also preserved in the Whymper collection.
I have received very beautiful and large leaves of the Castanea
which I have called C. Ungeri, from Alaska. I am now occupied in
working up this fossil Alaskan flora; the plants are in great part
drawn, and contain magnificent leaves. The treatise will be
published by the Swedish Academy in Stockholm; I hope to send you a
copy a few months hence. This flora is remarkable for its
resemblance to the European Miocene flora. The liquidambar, as well
as several poplars and willows, cannot be distinguished from those
of Oeningen; the same is true of an Elm, a Carpinus, and others. As
Alaska now belongs to the United States, it is to be hoped that
these collecting stations, which have already furnished such
magnificent plants, will be farther ransacked. . .Hoping that you
have returned safely from your journey, and that these lines may
find you well, I remain, with cordial greeting,
Sincerely yours,
OSWALD HEER.
Shortly after Agassiz's recovery, in July, 1868, he was invited by
Mr. Samuel Hooper to join a party of friends, tired members of
Congress and business men, on an excursion to the West, under
conditions which promised not only rest and change, but an
opportunity for studying glacial phenomena over a broad region of
prairie and mountain which Agassiz had never visited. They were to
meet at Chicago, keep on from there to St. Paul, and down the
Mississippi, turning off through Kansas to the eastern branch of
the Pacific Railroad, at the terminus of which they were to meet
General Sherman with ambulances and an escort for conveyance across
the country to the Union Pacific Railroad, returning then by
Denver, Utah, and Omaha, and across the State of Iowa to the
Mississippi once more. This journey was of great interest to
Agassiz, and its scientific value was heightened by a subsequent
stay of nearly two months at Ithaca, N.Y., on his return. Cornell
University was then just opened at Ithaca, and he had accepted an
appointment as non-resident professor, with the responsibility of
delivering annually a course of lectures on various subjects of
natural history. New efforts in behalf of education always
attracted him, and this drew him with an even stronger magnet than
usual, involving as it did an untried experiment--the attempt,
namely, to combine the artisan with the student, manual labor with
intellectual work. The plan was a generous one, and stimulated both
pupils and teachers. Among the latter none had greater sympathy
with the high ideal and broad humanity of the undertaking than
Agassiz.* (* Very recently a memorial tablet has been placed in the
Chapel at Cornell University by the trustees, recording their
gratitude for the share he took in the initiation of the
institution.)
Beside the enthusiasm which he brought to his special work, he
found an added pleasure at Cornell in the fact that the region in
which the new university was situated contained another chapter in
the book of glacial records he had so long been reading, and made
also, as the following letter tells us, a natural sequence to his
recent observations in the West.
TO M. DE LA RIVE.
ITHACA, October 26, 1868.
. . .I am passing some weeks here, and am studying the erratic
phenomena, and especially the formation of the many small lakes
which literally swarm in this region, and are connected in various
ways with the glacial epoch. The journey which I have just
completed has furnished me with a multitude of new facts concerning
the glacial period, the long continuance of which, and its
importance with reference to the physical history of the globe,
become daily more clear to me. The origin and mode of formation of
the vast system of our American rivers have especially occupied me,
and I think I have found the solution of the problem which they
present. This system reproduces the lines followed by the water
over the surface of the ground moraines, which covered the whole
continent, when the great sheet of ice which modeled the drift
broke up and melted away. This conclusion will, no doubt, be as
slow of acceptance as was the theory of the ancient extension of
glaciers. But that does not trouble me. For my own part I am
confident of its truth, and after having seen the idea of a glacial
epoch finally adopted by all except those who are interested in
opposing it on account of certain old and artificial theories, I
can wait a little till the changes which succeeded that epoch are
also understood. I have obtained direct proof that the prairies of
the West rest upon polished rock. It has happened in the course of
recent building on the prairie, that the native rock has been laid
bare here and there, and this rock is as distinctly furrowed by the
action of the glacier and by its engraving process, as the Handeck,
or the slopes of the Jura. I have seen magnificent slabs in
Nebraska in the basin of the river Platte. Do not the physicists
begin to think of explaining to us the probable cause of changes so
remarkable and so well established? We can no longer evade the
question by supposing these phenomena to be due to the action of
great currents. We have to do first with sheets of ice, five or six
thousand feet in thickness (an estimate which can be tested by
indirect measurements in the Northern States), covering the whole
continent, and then with the great currents which ensued upon the
breaking up of that mass of ice. He who does not distinguish
between these two series of facts, and perceive their connection,
does not understand the geology of the Quaternary epoch. . .
Of about this date is the following pleasant letter from Longfellow
to Agassiz. Although it has no special bearing upon what precedes,
it is inserted here, because their near neighborhood and constant
personal intercourse, both at Cambridge and Nahant, made letters
rare between them. Friends who see each other so often are
infrequent correspondents.
ROME, December 31, 1868.
MY DEAR AGASSIZ,
I fully intended to write you from Switzerland, that my letter
might come to you like a waft of cool air from a glacier in the
heat of summer. But alas! I did not find cool air enough for
myself, much less to send across the sea. Switzerland was as hot as
Cambridge, and all life was taken out of me; and the letter
remained in the inkstand. I draw it forth as follows.
One of the things I most wished to say, and which I say first, is
the delight with which I found your memory so beloved in England.
At Cambridge, Professor Sedgwick said, "Give my love to Agassiz.
Give him the blessing of an old man." In London, Sir Roderick
Murchison said, "I have known a great many men that I liked; but I
LOVE Agassiz." In the Isle of Wight, Darwin said, "What a set of
men you have in Cambridge! Both our universities put together
cannot furnish the like. Why, there is Agassiz,--he counts for
three."
One of my pleasantest days in Switzerland was that passed at
Yverdon. In the morning I drove out to see the Gasparins. In their
abundant hospitality they insisted upon my staying to dinner, and
proposed a drive up the valley of the Orbe. I could not resist; so
up the lovely valley we drove, and passed the old chateau of the
Reine Berthe, one of my favorite heroines, but, what was far more
to me, passed the little town of Orbe. There it stands, with its
old church tower and the trees on the terrace, just as when you
played under them as a boy. It was very, very pleasant to behold
. . .Thanks for your letter from the far West. I see by the papers
that you have been lecturing at the Cornell University.
With kindest greetings and remembrances, always affectionately
yours,
H.W.L.
CHAPTER 22.
1868-1871: AGE 61-64.
New Subscription to Museum.
Additional Buildings.
Arrangement of New Collections.
Dredging Expedition on Board the Bibb.
Address at the Humboldt Centennial.
Attack on the Brain.
Suspension of Work.
Working Force at the Museum.
New Accessions.
Letter from Professor Sedgwick.
Letter from Professor Deshayes.
Restored Health.
Hassler Voyage proposed.
Acceptance.
Scientific Preparation for the Voyage.
Agassiz returned to Cambridge to find the Museum on an improved
footing financially. The Legislature had given seventy-five
thousand dollars for an addition to the building, and private
subscriptions had doubled this sum, in order to provide for the
preservation and arrangement of the new collections. In
acknowledging this gift of the Legislature in his Museum Report for
1868 Agassiz says:--
"While I rejoice in the prospect of this new building, as affording
the means for a complete exhibition of the specimens now stored in
our cellars and attics and encumbering every room of the present
edifice, I yet can hardly look forward to the time when we shall be
in possession of it without shrinking from the grandeur of our
undertaking. The past history of our science rises before me with
its lessons. Thinking men in every part of the world have been
stimulated to grapple with the infinite variety of problems,
connected with the countless animals scattered without apparent
order throughout sea and land. They have been led to discover the
affinities of various living beings. The past has yielded up its
secrets, and has shown them that the animals now peopling the earth
are but the successors of countless populations which have preceded
them, and whose remains are buried in the crust of our globe.
Further study has revealed relations between the animals of past
time and those now living, and between the law of succession in the
former and the laws of growth and distribution in the latter, so
intimate and comprehensive that this labyrinth of organic life
assumes the character of a connected history, which opens before us
with greater clearness in proportion as our knowledge increases.
But when the museums of the Old World were founded, these relations
were not even suspected. The collections of natural history,
gathered at immense expense in the great centres of human
civilization, were accumulated mainly as an evidence of man's
knowledge and skill in exhibiting to the best advantage, not only
the animals, but the products and curiosities of all sorts from
various parts of the world. While we admire and emulate the
industry and perseverance of the men who collected these materials,
and did in the best way the work it was possible to do in their
time for science, we have no longer the right to build museums
after this fashion. The originality and vigor of one generation
become the subservience and indolence of the next, if we only
repeat the work of our predecessors. They prepared the ground for
us by accumulating the materials for extensive comparison and
research. They presented the problem; we ought to be ready with the
solution. If I mistake not, the great object of our museums should
be to exhibit the whole animal kingdom as a manifestation of the
Supreme Intellect. Scientific investigation in our day should be
inspired by a purpose as animating to the general sympathy, as was
the religious zeal which built the Cathedral of Cologne or the
Basilica of St. Peter's. The time is passed when men expressed
their deepest convictions by these wonderful and beautiful
religious edifices; but it is my hope to see, with the progress of
intellectual culture, a structure arise among us which may be a
temple of the revelations written in the material universe. If this
be so, our buildings for such an object can never be too
comprehensive, for they are to embrace the infinite work of
Infinite Wisdom. They can never be too costly, so far as cost
secures permanence and solidity, for they are to contain the most
instructive documents of Omnipotence."
Agassiz gave the winter of 1869 to identifying, classifying, and
distributing the new collections. A few weeks in the spring were,
however, passed with his friend Count de Pourtales in a dredging
expedition on board the Coast Survey Steamer Bibb, off the coast of
Cuba, on the Bahama Banks, and among the reefs of Florida. This
dredging excursion, though it covered a wider ground than any
previous one, was the third deep-sea exploration undertaken by M.
de Pourtales under the auspices of the Coast Survey. His
investigations may truly be said to have exercised a powerful
influence upon this line of research, and to have led the way to
the more extended work of the same kind carried on by the Coast
Survey in later years. He had long wished to show his old friend
and teacher some of the rich dredging grounds he had discovered
between Florida and the West Indies, and they thoroughly enjoyed
this short period of work together. Every day and hour brought some
new interest, and excess of material seemed the only difficulty.
This was Agassiz's last cruise in the Bibb, on whose hospitable
deck he had been a welcome guest from the first year of his arrival
in this country. The results of this expedition, as connected with
the present conformation of the continent and its probable
geological history in the past, were given as follows in the Museum
Bulletin of the same year.
REPORT UPON DEEP SEA DREDGINGS.*
(* "Bulletin of the Museum of Comparative Zoology" 1 Number 13 1869
pages 368, 369.)
BY LOUIS AGASSIZ.
From what I have seen of the deep-sea bottom, I am already led to
infer that among the rocks forming the bulk of the stratified crust
of our globe, from the oldest to the youngest formation, there are
probably none which have been formed in very deep waters. If this
be so, we shall have to admit that the areas now respectively
occupied by our continents, as circumscribed by the two hundred
fathom curve or thereabout, and the oceans at greater depth, have
from the beginning retained their relative outline and position;
the continents having at all times been areas of gradual upheaval
with comparatively slight oscillations of rise and subsidence, and
the oceans at all times areas of gradual depression with equally
slight oscillations. Now that the geological constitution of our
continent is satisfactorily known over the greatest part of its
extent, it seems to me to afford the strongest evidence that this
has been the case; while there is no support whatever for the
assumption that any part of it has sunk again to any very great
depth after its rise above the surface of the ocean. The fact that
upon the American continent, east of the Rocky Mountains, the
geological formations crop out in their regular succession, from
the oldest azoic and primordial deposits to the cretaceous
formation, without the slightest indication of a great subsequent
subsidence, seems to me the most complete and direct demonstration
of my proposition. Of the western part of the continent I am not
prepared to speak with the same confidence. Moreover, the position
of the cretaceous and tertiary formations along the low grounds
east of the Allegheny range is another indication of the permanence
of the ocean trough, on the margin of which these more recent beds
have been formed. I am well aware that in a comparatively recent
period, portions of Canada and the United States, which now stand
six or seven hundred feet above the level of the sea, have been
under water; but this has not changed the configuration of the
continent, if we admit that the latter is in reality circumscribed
by the two hundred fathom curve of depth.
The summer was passed in his beloved laboratory at Nahant (as it
proved, the last he ever spent there), where he was still
continuing the preparation of his work on sharks and skates. At the
close of the summer, he interrupted this occupation for one to
which he brought not only the reverence of a disciple, but a
life-long debt of personal gratitude and affection. He had been
entreated to deliver the address at the Humboldt Centennial
Celebration (September 15, 1869), organized under the auspices of
the Boston Society of Natural History. He had accepted the
invitation with many misgivings, for to literary work as such he
was unaccustomed, and in the field of the biographer he felt
himself a novice. His preparation for the task was conscientious
and laborious. For weeks he shut himself up in a room of the Public
Library in Boston and reviewed all the works of the great master,
living, as it were, in his presence. The result was a very concise
and yet full memoir, a strong and vigorous sketch of Humboldt's
researches, and of their influence not only upon higher education
at the present day, but on our most elementary instruction, until
the very "school-boy is familiar with his methods, yet does not
know that Humboldt is his teacher." Agassiz's picture of this
generous intellect, fertilizing whatever it touched, was made the
more life-like by the side lights which his affection for Humboldt
and his personal intercourse with him in the past enabled him to
throw upon it. Emerson, who was present, said of this address,
"that Agassiz had never delivered a discourse more wise, more
happy, or of more varied power." George William Curtis writes of
it: "Your discourse seems to me the very ideal of such an address,
--so broad, so simple, so comprehensive, so glowing, so profoundly
appreciative, telling the story of Humboldt's life and work as I am
sure no other living man can tell it." In memory of this occasion
the "Humboldt Scholarship" was founded at the Museum of Comparative
Zoology.
It is hardly worth while to consider now whether this effort, added
to the pressing work of the year, hastened the attack which
occurred soon after, with its warning to Agassiz that his
overtasked brain could bear no farther strain. The first seizure,
of short duration, but affecting speech and motion while it lasted,
was followed by others which became less and less acute until they
finally disappeared. For months, however, he was shut up in his
room, absolutely withdrawn from every intellectual effort, and
forbidden by his physicians even to think. The fight with his own
brain was his greatest difficulty, and perhaps he showed as much
power in compelling his active intellect to stultify itself in
absolute inactivity for the time, as he had ever shown in giving it
free rein. Yet he could not always banish the Museum, the
passionate dream of his American life. One day, after dictating
some necessary directions concerning it, he exclaimed, with a sort
of despairing cry, "Oh, my Museum! my Museum! always uppermost, by
day and by night, in health and in sickness, always--ALWAYS!"
He was destined, however, to a few more years of activity, the
reward, perhaps, of his patient and persistent struggle for
recovery. After a winter of absolute seclusion, passed in his sick
chamber, he was allowed by his physician, in the spring of 1870, to
seek change at the quiet village of Deerfield on the Connecticut
River. Nature proved the best physician. Unable when he arrived to
take more than a few steps without vertigo, he could, before many
weeks were over, walk several miles a day. Keen as an Egyptologist
for the hieroglyphics of his science, he was soon deciphering the
local inscriptions of the glacial period, tracking the course of
the ice on slab and dike and river-bed,--on every natural surface.
The old music sang again in his ear and wooed him back to life.
In the mean time, his assistants and students were doing all in
their power to keep the work of the Museum at high-water mark. The
publications, the classification and arrangement of the more recent
collections, the distribution of such portions as were intended for
the public, the system of exchanges, went on uninterruptedly. The
working force at the Museum was, indeed, now very strong. In great
degree it was, so to speak, home-bred. Agassiz had gradually
gathered about him, chiefly from among his more special students, a
staff of assistants who were familiar with his plans and shared his
enthusiasm. To these young friends he was warmly attached. It would
be impossible to name them all, but the knot of younger men who
were for years his daily associates in scientific work, whose
sympathy and cooperation he so much valued, and who are now in
their turn growing old in the service of science, will read the
roll-call between the lines, and know that none are forgotten here.
Years before his own death, he had the pleasure of seeing several
of them called to important scientific positions, and it was a
cogent evidence to him of the educational efficiency of the Museum,
that it had supplied to the country so many trained investigators
and teachers. Through them he himself teaches still. There was a
prophecy in Lowell's memorial lines:--
"He was a Teacher: why be grieved for him
Whose living word still stimulates the air?
In endless file shall loving scholars come,
The glow of his transmitted touch to share."
Beside these, there were several older, experienced naturalists,
who were permanently or transiently engaged at the Museum. Some
were heads of departments, while others lent assistance
occasionally in special work. Again the list is too long for
enumeration, but as the veteran among the older men Mr. J.G.
Anthony should be remembered. Already a conchologist of forty
years' standing when he came to the Museum in 1863, he devoted
himself to the institution until the day of his death, twenty years
later. Among those who came to give occasional help were Mr.
Lesquereux, the head of paleontological botany in this country; M.
Jules Marcou, the geologist; and M. de Pourtales, under whose care
the collection of corals was constantly improved and enlarged. The
last named became at last wholly attached to the Museum, sharing
its administration with Alexander Agassiz after his father's death.
To this band of workers some accessions had recently been made.
More than two years before, Agassiz had been so fortunate as to
secure the assistance of the entomologist, Dr. Hermann Hagen, from
Konigsberg, Prussia. He came at first only for a limited time, but
he remained, and still remains, at the Museum, becoming more and
more identified with the institution, beside filling a place as
professor in Harvard University. His scientific sympathy and
support were of the greatest value to Agassiz during the rest of
his life. A later new-corner, and a very important one at the
Museum, was Dr. Franz Steindachner, of Vienna, who arrived in the
spring of 1870 to put in final order the collection of Brazilian
fishes, and passed two years in this country. Thus Agassiz's hands
were doubly strengthened. Beside having the service of the salaried
assistants and professors, the Museum received much gratuitous aid.
Among the scientific volunteers were numbered for years Francois de
Pourtales, Theodore Lyman, James M. Barnard, and Alexander Agassiz,
while the business affairs of the institution were undertaken by
Thomas G. Cary, Agassiz's brother-in-law. The latter had long been
of great service to the Museum as collector on the Pacific coast,
where he had made this work his recreation in the leisure hours of
a merchant's life.* (* For the history of the Museum in later times
reference is made to the regular reports and publications of the
institution.)
Broken as he was in health, it is amazing to see the amount of work
done or directed by Agassiz during this convalescent summer of
1870. The letters written by him in this time concerning the Museum
alone would fill a good-sized volume. Such a correspondence is
unfit for reproduction here, but its minuteness shows that almost
the position of every specimen, and the daily, hourly work of every
individual in the Museum, were known to him. The details of
administration form, however, but a small part of the material of
this correspondence. The consideration and discussion of the future
of the Museum with those most nearly concerned, fill many of the
letters. They give evidence of a fostering and far-reaching care,
which provided for the growth and progress of the Museum, long
after his own share in it should have ceased.
In reviewing Agassiz's scientific life in the United States, its
brilliant successes, and the genial generous support which it
received in this country, it is natural to give prominence to the
brighter side. And yet it must not be forgotten that like all men
whose ideals outrun the means of execution, he had moments of
intense depression and discouragement. Some of his letters, written
at this time to friends who controlled the financial policy of the
Museum, are almost like a plea for life. While the trustees urge
safe investments and the expenditure of income alone, he believes
that in proportion to the growth and expansion of the Museum will
be its power of self-maintenance and its claim on the community at
large. In short, expenditure seemed to him the best investment,
insuring a fair return, on the principle that the efficiency and
usefulness of an institution will always be the measure of the
support extended to it. The two or three following letters, in
answer to letters from Agassiz which cannot be found, show how
earnestly, in spite of physical depression, he strove to keep the
Museum in relation with foreign institutions, to strengthen the
former, and cooperate as far as possible with the latter.
FROM PROFESSOR VON SIEBOLD.
MUNICH, 1869.
. . .Most gladly shall I meet your wishes both with regard to the
fresh-water fishes of Central Europe and to your desire for the
means of direct comparison between the fishes brought by Spix from
Brazil and described by you, and those you have recently yourself
collected in the Amazons. The former, with one exception, are still
in existence and remain undisturbed, for since your day no one has
cared to work at the fishes or reptiles. Schubert took no interest
in the zoological cabinet intrusted to him; and Wagner, who later
relieved him of its management, cared chiefly for the mammals. I
have now, however, given particular attention to the preservation
of everything determined by you, so far as it could be found, and
am truly glad that this material is again to be called into the
service of science. Of course I had to ask permission of the
"General Conservatorium of Scientific Collections" before sending
this property of the state on so long a journey. At my urgent
request this permission was very cordially granted by Herr von
Liebig, especially as our collection is likely to be increased by
the new forms you offer us.
As to the fresh-water fishes I must beg for a little time. At the
fish market, in April or May, I can find those Cyprinoids, the
males of which bear at the spawning season that characteristic
eruption of the skin, which has so often and so incorrectly led to
the making of new species. . .
From your son Alexander I receive one beautiful work after another.
Give him my best thanks for these admirable gifts, which I enter
with sincere pleasure in my catalogue of books. You are indeed
happy to have such a co-worker at your side. At the next
opportunity I shall write my thanks to him personally.
How is Dr. Hermann Hagen pleased with his new position? I think the
presence of this superior entomologist will exert a powerful and
important influence upon the development of entomology in North
America. . .
FROM PROFESSOR G.P. DESHAYES.
MUSEUM OF NATURAL HISTORY, PARIS, February 4, 1870.
Your letter was truly an event, my dear friend, not only for me but
for our Museum. . .How happy you are, and how enviable has been
your scientific career, since you have had your home in free
America! The founder of a magnificent institution, to which your
glorious name will forever remain attached, you have the means of
carrying out whatever undertaking commends itself to you as useful.
Men and things, following the current that sets toward you, are
drawn to your side. You desire, and you see your desires carried
out. You are the sovereign leader of the scientific movement around
you, of which you yourself have been the first promoter.
What would our old Museum not have gained in having at its head a
man like you! We should not now be lying stagnant in a space so
insufficient that our buildings, by the mere force of
circumstances, are transformed into store-houses, where objects of
study are heaped together, and can be of no use to any one. . .You
can fancy how much I envy your organization. It depressed me to
read your letter, with its brilliant proposals of exchange,
remembering how powerless we are to meet even a small number of
them. Your project is certainly an admirable one; to find the
scientific nomenclature where it is best established, and by the
help of good specimens transport it to your own doors. Nothing
could be better, and I would gladly assist in it. But to succeed in
this excellent enterprise one must have good duplicate specimens;
not having them, one must have money. As a conclusion to your
letter, the question of money was brought before my assembled
colleagues, but the answer was vague and uncertain. I must, then,
find resources in some other way, and this is what I propose to do
. . .[Here follow some plans for exchange.] Beside this, I will
busy myself in getting together authentic collections from our
French seas, both Oceanic and Mediterranean, and even from other
points in the European seas. Meantime, you shall have your share
henceforth in whatever comes to me. . .I learn from your son that
your health is seriously attacked. I was grieved to hear it. Take
care of yourself, my dear friend. You are still needed in this
world; you have a great work to accomplish, the end and aim of
which you alone are able to reach. You must, therefore, still stand
in the breach for some years to come.
Your letter, which shows me the countless riches you have to offer
at the Museum, puts me in the frame of mind of the child who was
offered his choice in a toy-shop. "I choose everything," he said. I
could reply in the same way. I choose all you offer me. Still, one
must be reasonable, and I will therefore name, as the thing I
chiefly desire, the remarkable fauna dredged from the Gulf Stream.
Let me add, however, in order to give you entire freedom, that
whatever you may send to the Museum will be received with sincere
and ardent gratitude.
And so, farewell, my dear friend, with a warm shake of the hand and
the most cordial regard.
DESHAYES.
The next is in answer to a letter from Agassiz to the veteran
naturalist, Professor Sedgwick, concerning casts of well-known
fossil specimens in Cambridge, England. Though the casts were
unattainable, the affectionate reply gave Agassiz keen pleasure.
FROM PROFESSOR ADAM SEDGWICK.
THE CLOSE, NORWICH, August 9, 1871.
MY VERY DEAR AND HONORED FRIEND,
. . .I of course showed your letter to my friend Seeley, and after
some consultation with men of practical knowledge, it was
considered almost impossible to obtain such casts of the reptilian
bones as you mention. The specimens of the bones are generally so
rugged and broken, that the artists would find it extremely
difficult to make casts from them without the risk of damaging
them, and the authorities of the university, who are the
proprietors of the whole collection in my Museum, would be
unwilling to encounter that risk. Mr. Seeley, however, fully
intends to send you a gutta-percha cast of the cerebral cavity of
one of our important specimens described in "Seeley's Catalogue,"
but he is full of engagements and may not hitherto have realized
his intentions. As for myself, at present I can do nothing except
hobble daily on my stick from my house to the Cathedral, for I am
afflicted by a painful lameness in my left knee. The load of years
begins to press upon me (I am now toiling through my 87th year),
and my sight is both dim and irritable, so that, as a matter of
necessity, I am generally compelled to employ an amanuensis. That
part is now filled by a niece who is to me in the place of a dear
daughter.
I need not tell you that the meetings of the British Association
are still continued, and the last session (this year at Edinburgh)
only ended yesterday. Let me correct a mistake. I met you first at
Edinburgh in 1834, the year I became Canon, and again at Dublin in
1835. . .It is a great pleasure to me, my dear friend, to see again
by the vision of memory that fine youthful person, that benevolent
face, and to hear again, as it were, the cheerful ring of the sweet
and powerful voice by which you made the old Scotchmen start and
stare, while you were bringing to life again the fishes of their
old red sandstone. I must be content with the visions of memory and
the feelings they again kindle in my heart, for it will never be my
happiness to see your face again in this world. But let me, as a
Christian man, hope that we may meet hereafter in heaven, and see
such visions of God's glory in the moral and material universe, as
shall reduce to a mere germ everything which has been elaborated by
the skill of man, or revealed to God's creatures. I send you an old
man's blessing, and remain,
Your affectionate friend,
ADAM SEDGWICK.
In November, 1870, Agassiz was able to return to Cambridge and the
Museum, and even to resume his lectures, which were as vigorous and
fresh as ever. So entirely did he seem to have recovered, that in
the course of the winter the following proposition was made to him
by his friend, Professor Benjamin Peirce, then Superintendent of
the Coast Survey.
FROM PROFESSOR PEIRCE.
COAST SURVEY OFFICE, WASHINGTON, February 18, 1871.
. . .I met Sumner in the Senate the day before yesterday, and he
expressed immense delight at a letter he had received from
Brown-Sequard, telling him that you were altogether free from
disease. . .Now, my dear friend, I have a very serious proposition
for you. I am going to send a new iron surveying steamer round to
California in the course of the summer. She will probably start at
the end of June. Would you go in her, and do deep-sea dredging all
the way round? If so, what companions will you take? If not, who
shall go?. . .
FROM AGASSIZ TO PROFESSOR PEIRCE.
CAMBRIDGE, February 20, 1871.
. . .I am overjoyed at the prospect your letter opens before me. Of
course I will go, unless Brown-Sequard orders me positively to stay
on terra firma. But even then, I should like to have a hand in
arranging the party, as I feel there never was, and is not likely
soon again to be, such an opportunity for promoting the cause of
science generally, and that of natural history in particular. I
would like Pourtales and Alex to be of the party, and both would
gladly join if they can. Both are as much interested about it as I
am, and I have no doubt between us we may organize a working team,
strong enough to do something creditable. It seems to me that the
best plan to pursue in the survey would be to select carefully a
few points (as many as time would allow) on shore, from which to
work at right angles with the coast, to as great a distance as the
results would justify, and then move on to some other head-land. If
this plan be adopted, it would be desirable to have one additional
observer to make collections on shore, to connect with the result
of the dredgings. This would be the more important as, with the
exception of Brazil, hardly anything is known of the shore faunae
upon the greater part of the South American coast. For shore
observations I should like a man of the calibre of Dr.
Steindachner, who has spent a year on the coast of Senegal, and
would thus bring a knowledge of the opposite side of the Atlantic
as a starting basis of comparison. . .
After consultation with his physicians, it was decided that Agassiz
might safely undertake the voyage in the Hassler, that it might
indeed be of benefit to his health. His party of naturalists, as
finally made up, consisted of Agassiz himself, Count de Pourtales,
Dr. Franz Steindachner, and Mr. Blake, a young student from the
Museum, who accompanied Agassiz as assistant and draughtsman. Dr.
Thomas Hill, ex-president of Harvard University, was also on the
expedition, and though engaged in special investigations of his
own, he joined in all the work with genial interest. The vessel was
commanded by Captain (now Commodore) Philip C. Johnson, whose
courtesy and kindness made the Hassler a floating home to the
guests on board. So earnest and active was the sympathy felt by him
and his officers in the scientific interests of the expedition,
that they might be counted as a valuable additional volunteer
corps. Among them should be counted Dr. William White, of
Philadelphia, who accompanied the expedition in a partly
professional, partly scientific capacity.
The hopes Agassiz had formed of this expedition, as high as those
of any young explorer, were only partially fulfilled. His
enthusiasm, though it had the ardor of youth, had none of its
vagueness. In a letter to Mr. Peirce, published in the Museum
Bulletin at this time, there is this passage: "If this world of
ours is the work of intelligence and not merely the product of
force and matter, the human mind, as a part of the whole, should so
chime with it, that from what is known it may reach the unknown. If
this be so, the knowledge gathered should, within the limits of
error which its imperfection renders unavoidable, enable us to
foretell what we are likely to find in the deepest abysses of the
sea." He looked, in short, for the solution of special problems
directly connected with all his previous work. He believed the
deeper sea would show forms of life akin to animals of earlier
geological times, throwing new light on the relation between the
fossil and the living world. In the letter above quoted, he even
named the species he expected to find most prevalent in those
greater depths: as, for instance, representatives of the older
forms of Ganoids and Selachians; Cephalopods, resembling the more
ancient chambered shells; Gasteropods, recalling the tertiary and
cretaceous types; and Acephala, resembling those of the jurassic
and cretaceous formations. He expected to find Crustaceans also,
more nearly approaching the ancient Trilobites than those now
living on the surface of the globe; and among Radiates he looked
for the older forms of sea-urchins, star-fishes, and corals.
Although the collections brought together on this cruise were rich
and interesting, they gave but imperfect answers to these
comprehensive questions. Owing to defects in the dredging
apparatus, the hauls from the greatest depths were lost.
With reference to the glacial period he anticipated still more
positive results. In the same letter the following passage occurs:
"There is, however, still one kind of evidence wanting, to remove
all doubt that the greater extension of glaciers in former ages was
connected with cosmic changes in the physical condition of our
globe. Namely, all the phenomena relating to the glacial period
must be found in the southern hemisphere, accompanied by the same
characteristic features as in the north, but with this essential
difference,--that everything must be reversed. The trend of the
glacial abrasions must be from the south northward, the lee-side of
abraded rocks must be on the north side of the hills and mountain
ranges, and the boulders must have traveled from the south to their
present position. Whether this be so or not, has not yet been
ascertained by direct observation. I expect to find it so
throughout the temperate and cold zones of the southern hemisphere,
with the exception of the present glaciers of Terra del Fuego and
Patagonia, which may have transported boulders in every direction.
Even in Europe, geologists have not yet sufficiently discriminated
between local glaciers and the phenomena connected with their
different degrees of successive retreat on the one hand; and, on
the other, the facts indicating the action of an extensive sheet of
ice moving over the whole continent from north to south. Among the
facts already known from the southern hemisphere are the so-called
rivers of stone in the Falkland Islands, which attracted the
attention of Darwin during his cruise with Captain Fitzroy, and
which have remained an enigma to this day. I believe it will not be
difficult to explain their origin in the light of the glacial
theory, and I fancy they may turn out to be ground moraines similar
to the 'horsebacks' in Maine.
"You may ask what this question of drift has to do with deep-sea
dredging? The connection is closer than may at first appear. If
drift is not of glacial origin, but is the product of marine
currents, its formation at once becomes a matter for the Coast
Survey to investigate. But I believe it will be found in the end,
that so far from being accumulated by the sea, the drift of the
Patagonian lowlands has been worn away by the sea to its present
outline, like the northern shores of South America and Brazil.". . .
This is not the place for a detailed account of the voyage of the
Hassler, but enough may be told to show something of Agassiz's own
share in it. A journal of scientific and personal experience, kept
by Mrs. Agassiz under his direction, was nearly ready for
publication at the time of his death. The two next chapters,
devoted to the cruise of the Hassler, are taken from that
manuscript. A portion of it appeared many years ago in the pages of
the "Atlantic Monthly."
CHAPTER 23.
1871-1872: AGE 64-65.
Sailing of the Hassler.
Sargassum Fields.
Dredging at Barbados.
From the West Indies to Rio de Janeiro.
Monte Video.
Quarantine.
Glacial Traces in the Bay of Monte Video.
The Gulf of Mathias.
Dredging off Gulf of St. George.
Dredging off Cape Virgens.
Possession Bay.
Salt Pool.
Moraine.
Sandy Point.
Cruise through the Straits.
Scenery.
Wind Storm.
Borja Bay.
Glacier Bay.
Visit to the Glacier.
Chorocua Bay.
The vessel was to have started in August, but, owing to various
delays in her completion, she was not ready for sea until the late
autumn. She finally sailed on December 4, 1871, on a gray
afternoon, which ushered in the first snow-storm of the New England
winter. Bound for warmer skies, she was, however, soon in the
waters of the Gulf Stream, where the work of collecting began in
the fields of Sargassum, those drifting, wide-spread expanses of
loose sea-weed carrying a countless population, lilliputian in
size, to be sure, but very various in character. Agassiz was no
less interested than other naturalists have been in the old
question so long asked and still unanswered, about the Sargassum.
"Where is its home, and what its origin? Does it float, a rootless
wanderer on the deep, or has it broken away from some submarine
attachment?" He had passed through the same region before, in going
to Brazil, but then he was on a large ocean steamer, while from the
little Hassler, of 360 tons, one could almost fish by hand from the
Sargassum fields. Some of the chief results are given in the
following letter.
TO PROFESSOR PEIRCE.
ST. THOMAS, December 15, 1871.
. . .As soon as we reached the Gulf Stream we began work. Indeed,
Pourtales had organized a party to study the temperatures as soon
as we passed Gay Head, and will himself report to you his results.
My own attention was entirely turned to the Gulf weed and its
inhabitants, of which we made extensive collections. Our
observations on the floating weed itself favor the view of those
who believe it to be torn from rocks, on which Sargassum naturally
grows. I made a simple experiment which seems to me conclusive. Any
branch of the sea-weed which is deprived of its FLOATS sinks at
once to the bottom of the water, and these floats are not likely to
be the first parts developed from the spores. Moreover, after
examining large quantities of the weed, I have not seen a single
branch, however small, which did not show marks of having been torn
from a solid attachment.
You may hardly feel an interest in my zoological observations, but
I am sure you will be glad to learn that we had the best
opportunity of carefully examining most of the animals known to
inhabit the Gulf weed, and some also which I did not know to occur
among them. The most interesting discovery of our voyage thus far,
however, is that of a nest built by a fish, and floating on the
broad ocean with its living freight. On the 13th, Mr. Mansfield,
one of our officers, brought me a ball of Gulf weed which he had
just picked up, and which excited my curiosity to the utmost. It
was a round mass of Sargassum about the size of two fists. The bulk
of the ball was made up of closely packed branches and leaves, held
together by fine threads, running through them in every direction,
while other branches hung more loosely from the margin. Placed in a
large bowl of water it became apparent that the loose branches
served to keep the central mass floating, cradle-like, between
them. The elastic threads, which held the ball of Gulf weed
together, were beaded at intervals, sometimes two or three beads
close together, or a bunch of them hanging from the same cluster of
threads, or occasionally scattered at a greater distance from each
other. Nowhere was there much regularity in the distribution of the
beads. They were scattered pretty uniformly throughout the whole
ball of seaweed, and were themselves about the size of an ordinary
pin's head. Evidently we had before us a nest of the most curious
kind, full of eggs. What animal could have built this singular
nest? It did not take long to ascertain the class to which it
belonged. A common pocket lens revealed at once two large eyes on
the side of the head, and a tail bent over the back of the body, as
in the embryo of ordinary fishes shortly before the period of
hatching. The many empty egg cases in the nest gave promise of an
early opportunity of seeing some embryos, freeing themselves from
their envelope. Meanwhile a number of these eggs containing live
embryos were cut out of the nest and placed in separate glass jars,
in order to multiply the chances of preserving them; while the nest
as a whole was secured in alcohol, as a memorial of our discovery.
The next day I found two embryos in my glass jars; they moved
occasionally in jerks, and then rested a long time motionless on
the bottom of the jar. On the third day I had over a dozen of these
young fishes, the oldest beginning to be more active. I need not
relate in detail the evidence I soon obtained that these embryos
were actually fishes. . .But what kind of fish was it? At about the
time of hatching, the fins differ too much from those of the adult,
and the general form has too few peculiarities, to give any clew to
this problem. I could only suppose it would prove to be one of the
pelagic species of the Atlantic. In former years I had made a
careful study of the pigment cells of the skin in a variety of
young fishes, and I now resorted to this method to identify my
embryos. Happily we had on board several pelagic fishes alive. The
very first comparison I made gave the desired result. The pigment
cell of a young Chironectes pictus proved identical with those of
our little embryos. It thus stands, as a well authenticated fact,
that the common pelagic Chironectes of the Atlantic, named Ch.
pictus by Cuvier, builds a nest for its eggs in which the progeny
is wrapped up with the materials of which the nest itself is
composed; and as these materials consist of the living Gulf weed,
the fish cradle, rocking upon the deep ocean, is carried along as
in an arbor, which affords protection and afterwards food also, to
its living freight. This marvelous story acquires additional
interest, when we consider the characteristic peculiarities of the
genus Chironectes. As its name indicates, it has fin-like hands;
that is to say, the pectoral fins are supported by a kind of long
wrist-like appendage, and the rays of the ventrals are not unlike
rude fingers. With these limbs these fishes have long been known to
attach themselves to sea-weeds, and rather to walk than to swim in
their natural element. But now that we know their mode of
reproduction, it may fairly be asked if the most important use of
their peculiarly constructed fins is not the building of their
nest?. . .There thus remains one closing chapter to the story. May
some naturalist, becalmed among the Gulf weed, have the good
fortune to witness the process by which the nest is built. . .
This whole investigation was of the greatest interest to Agassiz,
and, coming so early in the voyage, seemed a pleasant promise of
its farther opportunities. The whole ship's company soon shared his
enthusiasm, and the very sailors gathered about him in the
intervals of their work, or hung on the outskirts of the scientific
circle. A pause of a few days was made at one or two of the West
Indian islands, at St. Thomas and Barbados. At the latter, the
first cast of the large dredge was made on a ledge of shoals in a
depth of eighty fathoms, and, among countless other things, a
number of stemmed crinoids and comatulae were brought up. An ardent
student of the early fossil echinoderms, it was a great pleasure to
Agassiz to gather their fresh and living representatives. It was
like turning a leaf of the past and finding the subtle thread which
connects it with the present.
TO PROFESSOR PEIRCE.
PERNAMBUCO, January 16, 1872.
MY DEAR PEIRCE,
I should have written to you from Barbados, but the day before we
left the island was favorable for dredging, and our success in that
line was so unexpectedly great, that I could not get away from the
specimens, and made the most of them for study while I had the
chance. We made only four hauls, in between seventy-five and one
hundred and twenty fathoms. But what hauls! Enough to occupy half a
dozen competent zoologists for a whole year, if the specimens could
be kept fresh for that length of time. The first haul brought up a
Chemidium-like sponge; the next gave us a crinoid, very much like
the Rhizocrinus lofotensis, but probably different; the third, a
living Pleurotomaria; the fourth, a new genus of Spatangoids, etc.,
etc., not to speak of the small fry. We had the crinoid alive for
ten or twelve hours. When contracted, the pinnules are pressed
against the arms, and the arms themselves shut against one another,
so that the whole looks like a swash made up of a few long, coarse
twines. When the animal opens, the arms at first separate without
bending outside, so that the whole looks like an inverted pentapod;
but gradually the tips of the arms bend outward as the arms diverge
more and more, and when fully expanded the crown has the appearance
of a lily of the L. martagon type, in which each petal is curved
upon itself, the pinnules of the arms spreading laterally more and
more, as the crown is more fully open. I have not been able to
detect any motion in the stem traceable to contraction, though
there is no stiffness in its bearing. When disturbed, the pinnules
of the arms first contract, the arms straighten themselves out, and
the whole gradually and slowly closes up. It was a very impressive
sight for me to watch the movements of the creature, for it not
only told of its own ways, but at the same time afforded a glimpse
into the countless ages of the past, when these crinoids, so rare
and so rarely seen nowadays, formed a prominent feature of the
animal kingdom. I could see, without great effort of the
imagination, the shoal of Lockport teeming with the many genera of
crinoids which the geologists of New York have rescued from that
prolific Silurian deposit, or recall the formations of my native
country, in the hill-sides of which also, among fossils indicating
shoal water deposits, other crinoids abound, resembling still more
closely those we find in these waters. The close affinities of
Rhizocrinus with Apiocrinoids are further exemplified by the fact
that when the animal dies, it casts off its arms, like Apiocrinus,
the head of which is generally found without arms. And now the
question may be asked, what is the meaning of the occurrence of
these animals in deep waters at the present day, when, in former
ages, similar types inhabited shallow seas? Of the fact there can
be no doubt, for it is not difficult to adduce satisfactory
evidence of the shoal-like character of the Silurian deposits of
the State of New York; their horizontal position, combined with the
gradual recession of the higher beds in a southerly direction,
leaves no doubt upon this point; and in the case of the jurassic
formation alluded to above, the combination of the crinoids with
fossils common upon coral reefs, and their presence in atolls of
that period, are satisfactory proofs of my assertion. What does it
mean, then, when we find the Pentacrinus and Rhizocrinus of the
West Indies in deep water only? It seems to me that there is but
one explanation of the fact, namely, that in the progress of the
earth's growth, we must look for such a displacement of the
conditions favorable to the maintenance of certain lower types, as
may recall most fully the adaptations of former ages. It was in
this sense I alluded, in my first letter to you, to the probability
of our finding in deeper water representatives of earlier
geological types; and if my explanation is correct, my anticipation
is also fully sustained. But do the deeper waters of the present
constitution of our globe really approximate the conditions for the
development of animal life, which existed in the shallower seas of
past geological ages? I think they do, or at least I believe they
approach it as nearly as anything can in the present order of
things upon earth; for the depths of the ocean alone can place
animals under a pressure corresponding to that caused by the heavy
atmosphere of earlier periods. But, of course, such high pressure
as animals meet in great depths cannot be a favorable condition for
the development of life; hence the predominance of lower forms in
the deep sea. The rapid diminution of light with the increasing
depth, and the small amount of free oxygen in these waters under
greater and greater pressure, not to speak of other limitations
arising from the greater uniformity of the conditions of existence,
the reduced amount and less variety of nutritive substances, etc.,
etc., are so many causes acting in the same direction and with
similar results. For all these reasons, I have always expected to
find that the animals living in great depths would prove to be of a
standing, in the scale of structural complications, inferior to
those found in shoal waters or near shore; and the correlation
elsewhere pointed out between the standing of animals and their
order of succession in geological times (see "Essay on
Classification ") justifies another form of expression of these
facts, namely, that in deeper waters we should expect to find
representatives of earlier geological periods. There is in all this
nothing which warrants the conclusion that any of the animals now
living are lineal descendants of those of earlier ages; nor does
their similarity to those of earlier periods justify the statement
that the cretaceous formation is still extant. It would be just as
true to nature to say that the tertiaries are continued in the
tropics, on account of the similarity of the miocene mammalia to
those of the torrid zone.
We have another case in the Pleurotomaria. It is not long since it
has been made known that the genus Pleurotomaria is not altogether
extinct, a single specimen having been discovered about ten years
ago in the West Indies. Even Pictet, in the second edition of his
Paleontology, still considers Pleurotomaria as extinct, and as
belonging to the fossiliferous formations which extend from the
Silurian period to the Tertiary. Of the living species found at
Marie Galante, nothing is known except the specific characteristics
of the shell. We dredged it in one hundred and twenty fathoms, on
the west side of Barbados, alive, and kept it alive for twenty-four
hours, during which time the animal expanded and showed its
remarkable peculiarities. It is unquestionably the type of a
distinct family, entirely different from the other Mollusks with
which it has been hitherto associated. Mr. Blake has made fine
colored drawings of it, which may be published at some future
time. . .The family of the Pleurotomariae numbers between four and
five hundred fossil species, beginning in the Silurian deposits, but
especially numerous in the carboniferous and jurassic formations.
The sponges afford another interesting case. When the first number
of the great work of Goldfuss, on the fossils of Germany, made its
appearance, about half a century ago, the most novel types it made
known were several genera of sponges from the jurassic and
cretaceous beds, described under the names of Siphonia, Chemidium,
and Scyphia. Nothing of the kind has been known among the living to
this day; and yet, the first haul of the dredge near Barbados gave
us a Chemidium, or, at least, a sponge so much like the fossil
Chemidium, that it must remain for future comparisons to determine
whether there are any generic differences between our living sponge
and the fossil. The next day brought us a genuine Siphonia, another
genus thus far only known from the jurassic beds; and it is worth
recording, that I noticed in the collection of Governor Rawson
another sponge,--brought to him by a fisherman who had caught it on
his line, on the coast of Barbados,--which belongs to the genus
Scyphia. Thus the three characteristic genera of sponges from the
secondary formation, till now supposed to be extinct, are all three
represented in the deep waters of the West Indies. . .
Another family of organized beings offers a similar testimony to
that already alluded to. If there is a type of Echinoderms
characteristic of a geological period, it is the genus Micraster of
the cretaceous formation, in its original circumscription. No
species of this genus is known to have existed during the Tertiary
era, and no living species has as yet been made known. You may
therefore imagine my surprise when the dredge first yielded three
specimens of a small species of that particular group of the genus,
which is most extensively represented in the upper cretaceous beds.
Other examples of less importance might be enumerated; suffice it
now to add that my expectation of finding in deep waters animals
already known, but thus far exceedingly rare in museums, is already
in a measure realised. . .
Little can be said of the voyage from the West Indies to Rio de
Janeiro. It had the usual vicissitudes of weather, with here and
there a flight (so it might justly be called) of flying-fish, a
school of porpoises or dog-fish, or a sail in the distance, to
break the monotony. At Rio de Janeiro it became evident that the
plan of the voyage must be somewhat curtailed. This was made
necessary partly by the delays in starting,--in consequence of
which the season would be less favorable than had been anticipated
along certain portions of the proposed route,--and partly by the
defective machinery, which had already given some trouble to the
Captain. The Falkland Islands, the Rio Negro, and the Santa Cruz
rivers were therefore renounced; with what regret will be
understood by those who know how hard it is to be forced to break
up a scheme of work, which was originally connected in all its
parts. The next pause was at Monte Video; but as there was a strict
quarantine, Agassiz was only allowed to land at the Mount, a hill
on the western side of the bay, the geology of which he was anxious
to examine. He found true erratics--loose pebbles, granite, gneiss,
and granitic sandstone, having no resemblance to any native rock in
the vicinity--scattered over the whole surface of the hill to its
very summit. The hill itself had also the character of the "roches
moutonnees" modeled by ice in the northern hemisphere. As these
were the most northern erratics and glaciated surfaces reported in
the southern hemisphere, the facts there were very interesting to
him.
With dredgings off the Rio de la Plata, and along the coast between
that and the Rio Negro, the vessel held on her way to the Gulf of
Mathias, a deep, broad bay running some hundred miles inland, and
situated a little south of the Rio Negro. Here some necessary
repairs enforced a pause, of which Agassiz took advantage for
dredging and for studying the geology of the cliffs along the north
side of the bay. As seen from the vessel, they seemed to be
stratified with extraordinary evenness and regularity to within a
few feet of the top, the summit being crowned with loose sand.
Farther on, they sank to sand dunes piled into rounded banks and
softly moulded ledges, like snow-drifts. Landing the next day at a
bold bluff marked Cliff End on the charts, he found the lower
stratum to consist of a solid mass of tertiary fossils, chiefly
immense oysters, mingled, however, with sea-urchins. Superb
specimens were secured,--large boulders crowded with colossal
shells and perfectly preserved echini. From the top of the cliff,
looking inland, only a level plain was seen, stretching as far as
the eye could reach, broken by no undulations, and covered with
low, scrubby growth. The seine was drawn on the beach, and yielded
a good harvest for the fish collection. At evening the vessel
anchored at the head of the bay, off the Port of San Antonio. The
name would seem to imply some settlement; but a more lonely spot
cannot be imagined. More than thirty years ago, Fitzroy had sailed
up this bay, partially surveyed it, and marked this harbor on his
chart. If any vessel has broken the loneliness of its waters since,
no record of any such event has been kept. Of the presence of man,
there was no sign. Yet the few days passed there were among the
pleasantest of the voyage to Agassiz. The work of the dredge and
seine was extremely successful, and the rambles inland were
geological excursions of great interest. Here he had the first
sight of the guanaco of the Patagonian plains. The weather was
fine, and at night-fall, to the golden light of sunset succeeded
the fitful glow, over land and water, of the bonfires built by the
sailors on the beach. Returning to the ship after dark, the various
parties assembled in the wardroom, to talk over the events of the
day and lay out plans for the morrow. These are the brightest hours
in such a voyage, when the novelty of the locality gives a zest to
every walk or row, and all are full of interest in a new and
exciting life. One is more tolerant even of monotonous natural
features in a country so isolated, so withdrawn from human life and
occupation. The very barrenness seems in harmony with the intense
solitude.
The Hassler left her anchorage on this desolate shore on an evening
of singular beauty. It was difficult to tell when she was on her
way, so quietly did she move through the glassy waters, over which
the sun went down in burnished gold, leaving the sky without a
cloud. The light of the beach fires followed her till they too
faded, and only the phosphorescence of the sea attended her into
the night. Rough and stormy weather followed this fair start, and
only two more dredgings were possible before reaching the Strait of
Magellan. One was off the Gulf of St. George, where gigantic
star-fishes seemed to have their home. One of them, a superb
basket-fish, was not less than a foot and a half in diameter; and
another, like a huge sunflower of reddish purple tint, with
straight arms, thirty-seven in number, radiating from the disk, was
of about the same size. Many beautiful little sea-urchins came up
in the same dredging. About fifty miles north of Cape Virgens, in
tolerably calm weather, another haul was tried, and this time the
dredge returned literally solid with Ophiurans.
On Wednesday, March 13th, on a beautifully clear morning, like the
best October weather in New England, the Hassler rounded Cape
Virgens and entered the Strait of Magellan. The tide was just on
the flood, and all the conditions favorable for her run to her
first anchorage in the Strait at Possession Bay. Here the working
force divided, to form two shore parties, one of which, under
Agassiz's direction, the reader may follow. The land above the
first shore bluff at Possession Bay rises to a height of some four
hundred feet above the sea-level, in a succession of regular
horizontal terraces, of which Agassiz counted eight. On these
terraces, all of which are built, like the shore-bluffs, of
tertiary deposits, were two curious remnants of a past state of
things. The first was a salt-pool lying in a depression on the
second terrace, some one hundred and fifty feet above the sea. This
pool contained living marine shells, identical with those now found
along the shore. Among them were Fusus, Mytilus, Buccinum,
Fissurella, Patella, and Voluta, all found in the same numeric
relations as those in which they now exist upon the beach below.
This pool is altogether too high to be reached by any tidal
influence, and undoubtedly indicates an old sea-level, and a
comparatively recent upheaval of the shore. The second was a
genuine moraine, corresponding in every respect to those which
occur all over the northern hemisphere. Agassiz came upon it in
ascending to the third terrace above the salt-pool and a little
farther inland. It had all the character of a terminal moraine in
contact with an actual glacier. It was composed of heterogeneous
materials,--large and small pebbles and boulders impacted together
in a paste of clayey gravel and sand. The ice had evidently
advanced from the south, for the mass had been pushed steeply up on
the southern side, and retained so sharp an inclination on that
face that but little vegetation had accumulated upon it. The
northern side, on the contrary, was covered with soil and
overgrown; it sloped gently off,--pebbles and larger stones being
scattered beyond it. The pebbles and boulders of this moraine were
polished, scratched, and grooved, and bore, in short, all the usual
marks of glacial action. Agassiz was naturally delighted with this
discovery. It was a new link in the chain of evidence, showing that
the drift phenomena are connected at the south as well as at the
north with the action of ice, and that the frozen Arctic and
Antarctic fields are but remnants of a sheet of ice, which has
retreated from the temperate zones of both hemispheres to the polar
regions. The party pushed on beyond the moraine to a hill of
considerable height, which gave a fine view of the country toward
Mount Aymon and the so-called Asses' Ears. They brought back a
variety of game, but their most interesting scientific acquisitions
were boulders from the moraine scored with glacial characters, and
shells from the salt pool.
Still accompanied by beautiful weather, the Hassler anchored at the
Elizabeth Islands and at San Magdalena. Here Agassiz had an
opportunity of examining the haunts and rookeries of the penguins
and cormorants, and obtaining fine specimens of both. As the
breeding places and the modes of life of these animals have been
described by other travelers, there is nothing new to add from his
impressions, until the vessel anchored, on the 16th March, before
Sandy Point, the only permanent settlement in the Strait.
Here there was a pause of several days, which gave Agassiz an
opportunity to draw the seine with large results for his marine
collections. By the courtesy of the Governor, he had also an
opportunity of making an excursion along the road leading to the
coal-mines. The wooded cliffs, as one ascends the hills toward the
mines, are often bold and picturesque, and Agassiz found that
portions of them were completely built of fossil shells. There is
an oyster-bank, some one hundred feet high, overhanging the road in
massive ledges that consist wholly of oyster-valves, with only
earth enough to bind them together. He was inclined, from the
character of the shells, to believe that the coal must be
cretaceous rather than tertiary.
On Tuesday, the 19th March, the Hassler left Sandy Point. The
weather was beautiful,--a mellow autumn day with a reminiscence of
summer in its genial warmth. The cleft summit of Sarmiento was
clear against the sky, and the snow-fields, swept over by alternate
light and shadow, seemed full of soft undulations. The evening
anchorage was in the Bay of Port Famine, a name which marks the
site of Sarmiento's ill-fated colony, and recalls the story of the
men who watched and waited there for the help that never came. The
stay here was short, and Agassiz spent the time almost wholly in
studying the singularly regular, but completely upturned strata
which line the beach, with edges so worn down as to be almost
completely even with each other.
For many days after this, the Hassler pursued her course, past a
seemingly endless panorama of mountains and forests rising into the
pale regions of snow and ice, where lay glaciers in which every
rift and crevasse, as well as the many cascades flowing down to
join the waters beneath, could be counted as she steamed by them.
Every night she anchored in the sheltered harbors formed by the
inlets and fords which break the base of the rocky walls, and often
lead into narrower ocean defiles penetrating, one knows not
whither, into the deeper heart of these great mountain masses.
These were weeks of exquisite delight to Agassiz. The vessel often
skirted the shore so closely that its geology could be studied from
the deck. The rounded shoulders of the mountains, in marked
contrast to their peaked and jagged crests, the general character
of the snow-fields and glaciers, not crowded into narrow valleys as
in Switzerland, but spread out on the open slopes of the loftier
ranges, or, dome like, capping their summits,--all this afforded
data for comparison with his past experience, and with the
knowledge he had accumulated upon like phenomena in other regions.
Here, as in the Alps, the abrupt line, where the rounded and worn
surfaces of the mountains (moutonnees, as the Swiss say) yield to
their sharply cut, jagged crests, showed him the ancient and
highest line reached by the glacial action. The long, serrated edge
of Mount Tarn, for instance, is like a gigantic saw, while the
lower shoulders of the mass are hummocked into a succession of
rounded hills. In like manner the two beautiful valleys, separated
by a bold bluff called Bachelor's Peak, are symmetrically rounded
on their slopes, while their summits are jagged and rough.
On one occasion the Hassler encountered one of those sudden and
startling flaws of wind common to the Strait. The breeze, which had
been strong all day, increased with sudden fury just as the vessel
was passing through a rather narrow channel, which gave the wind
the additional force of compression. In an inconceivably short
time, the channel was lashed into a white foam; the roar of wind
and water was so great you could not hear yourself speak, though
the hoarse shout of command and the answering cry of the sailors
rose above the storm. To add to the confusion, a loose sail slatted
as if it would tear itself in pieces, with that sharp, angry,
rending sound which only a broad spread of loose canvas can make.
It became impossible to hold the vessel against the amazing power
of the blast, and the Captain turned her round with the intention
of putting her into Borja Bay, not far from which, by good fortune,
she chanced to be. As she came broadside to the wind in turning, it
seemed as if she must be blown over, so violently did she careen.
Once safely round, she flew before the wind, which now became her
ally instead of her enemy, and by its aid she was soon abreast of
Borja Bay. Never was there a more sudden transition from chaos to
peace than that which ensued as she turned in from the tumult in
the main channel to the quiet waters of the bay. The Hassler almost
filled the tiny harbor shut in between mountains. She lay there
safe and sheltered in breathless calm, while the storm raged and
howled outside. These frequent, almost land-locked coves, are the
safety of navigators in these straits; but after this day's
experience, it was easy to understand how sailing vessels may be
kept waiting for months between two such harbors, struggling vainly
to make a few miles and constantly driven back by sudden squalls.
In this exquisite mountain-locked harbor, the vessel was
weather-bound for a couple of days. Count Pourtales availed himself
of this opportunity to ascend one of the summits. Up to a height of
fifteen hundred feet, the rock was characterized by the smoothed,
rounded surfaces which Agassiz had observed along his whole route
in the Strait. Above that height all was broken and rugged, the
line of separation being as defined as on any valley wall in
Switzerland. It was again impossible to decide, on such short
observation, whether these effects were due to local glacial
action, or whether they belonged to an earlier general ice-period.
But Agassiz became satisfied, as he advanced, that the two sets of
phenomena existed together, as in the northern hemisphere. The
general aspect of the opposite walls of the Strait confirmed him in
the idea that the sheet of ice in its former extension had advanced
from south to north, grinding its way against and over the southern
wall to the plains beyond. In short, he was convinced that, as a
sheet of ice has covered the northern portion of the globe, so a
sheet of ice has covered also the southern portion, advancing, in
both instances, far toward the equatorial regions. His observations
in Europe, in North America, and in Brazil seemed here to have
their closing chapter.
With these facts in his mind, he did not fail to pause before
Glacier Bay, noted for its immense glacier, which seems, as seen
from the main channel, to plunge sheer down into the waters of the
bay. A boat party was soon formed to accompany him to the glacier.
It proved less easy of access than it looked at a distance. A broad
belt of wood, growing, as Agassiz afterward found, on an
accumulation of old terminal moraines, spanned the lower valley
from side to side. Through this wood there poured a glacial river,
emptying itself into the bay. Strange to say, this glacier-washed
forest, touching the ice on one side and the sea on the other, was
full of flowers. The red bells of the glossy-leaved Desfontainia,
the lovely pink blossoms of the Phylesia, the crimson berries of
the Pennetia, stood out in bright relief from a background of mossy
tree-trunks and rocks. After an hour's walking, made laborious by
the spongy character of the ground,--a mixture of loose soil and
decaying vegetation, in which one sank knee-deep,--the gleam of the
ice began to shimmer through the trees; and issuing from the wood,
the party found themselves in front of a glacier wall, stretching
across the whole valley and broken into deep rifts, caves, and
crevasses of dark blue ice. The glacier was actually about a mile
wide; but as the central portion was pressed forward in advance of
the sides, the whole front was not presented at once. It formed a
sharp crescent, with the curve turned outward. One of the caves in
this front wall was some thirty or forty feet high, about a hundred
feet deep, and two or three yards wide at the entrance. At the
further end it narrowed to a mere gallery, where the roof was
pierced by a circular window, quite symmetrical in shape, through
which one looked up to the blue sky and drifting clouds. There must
be strange effects in this ice-cavern, when the sun is high and
sends a shaft of light through its one window to illuminate the
interior.
This first excursion was a mere reconnaissance. An approximate idea
of the dimensions of the glacier, and some details of its
structure, were obtained on a second visit the following day. The
anchorage for the night was in Playa Parda Cove, one of the most
beautiful of the many beautiful harbors of the Magellan Strait. It
is entered by a deep, narrow slit, cut into the mountains on the
northern side of the Strait, and widening at its farther end into a
kind of pocket or basin, hemmed in between rocky walls bordered by
forests, and overhung by snow and ice-fields. The next morning at
half-past three o'clock, just as moonlight was fading before the
dawn, and the mountains were touched with the coming day, the
reveille was sounded for those who were to return to Glacier Bay.
This time Agassiz divided his force so that they could act
independently of each other, though under a general plan laid out
by him. M. de Pourtales and Dr. Steindachner ascended the mountain
to the left of the valley, following its ridge, in the hope of
reaching a position from which they could discover the source and
the full length of the glacier. In this they did not succeed,
though M. de Pourtales estimated its length, as far as he could see
from any one point, to be about three miles, beyond which it was
lost in the higher range. It made part of a net-work of glaciers
running back into a large massif of mountains, and fed by many a
neve on their upper slopes. The depth as well as the length of this
glacier remains somewhat problematical, and indeed all the
estimates in so cursory a survey must be considered as
approximations rather than positive results. The glazed surface of
the ice is an impediment to any examination from the upper side. It
would be impossible to spring from brink to brink of a crevasse, as
is so constantly done by explorers of Alpine glaciers where the
edges of the cracks are often snowy or granular. Here the edges of
the crevasses are sharp and hard, and to spring across one of any
size would be almost certain death. There is no hold for an Alpine
stock, no grappling point for hands or feet. Any investigation from
the upper surface would, therefore, require special apparatus, and
much more time than Agassiz and his party could give. Neither was
an approach from the side very easy. The glacier arches so much in
the centre, and slopes away so steeply, that when one is in the
lateral depression between it and the mountain, one faces an almost
perpendicular wall of ice, which blocks the vision completely. M.
de Pourtales measured one of the crevasses in this wall, and found
that it had a depth of some seventy feet. Judging from the
remarkable convexity of the glacier, it can hardly be less in the
centre than two or three times its thickness on the edges,
--something over two hundred feet, therefore. Probably none of
these glaciers of the Strait of Magellan are as thick as those of
Switzerland, though they are often much broader. The mountains are
not so high, the valleys not so deep, as in the Alps; the ice is
consequently not packed into such confined troughs. By some of the
party an attempt was made to ascertain the rate of movement,
signals having been adjusted the day before for its measurement.
During the middle of the day, it advanced at the rate of ten inches
and a fraction in five hours. One such isolated observation is of
course of little comparative value. For himself, Agassiz reserved
the study of the bay, the ancient bed of the glacier in its former
extension. He spent the day in cruising about the bay in the
steam-launch, landing at every point he wished to investigate. His
first care was to examine minutely the valley walls over which the
glacier must once have moved. Every characteristic feature, known
in the Alps as the work of the glaciers, was not only easily
recognizable here, but as perfectly preserved as anywhere in
Switzerland. The rounded knolls to which De Saussure first gave the
name of roches moutonnees were smoothed, polished, scratched, and
grooved in the direction of the ice movement, the marks running
mostly from south to north, or nearly so. The general trend of the
scratches and furrows showed them to have been continuous from one
knoll to another. The furrows were of various dimensions, sometimes
shallow and several inches broad, sometimes narrow with more
defined limits, gradually passing into mere lines on a very
smoothly polished surface. Even the curious notches scooped out of
the even surfaces, and technically called "coups de gouge," were
not wanting. In some places the seams of harder rock stood out for
a quarter of an inch or so above adjoining decomposed surfaces; in
such instances the dike alone retained the glacial marks, which had
been worn away from the softer rock.
The old moraines were numerous and admirably well preserved.
Agassiz examined with especial care one colossal lateral moraine,
standing about two miles below the present terminus of the ice and
five hundred feet above the sea-level. It consisted of the same
rocks as those found on the present terminal moraine, part of them
being rounded and worn, while large, angular boulders rested above
the smaller materials. This moraine forms a dam across a trough in
the valley wall, and holds back the waters of a beautiful lake,
about a thousand feet in length and five hundred in width, shutting
it in just as the Lake of Meril in Switzerland is held in its basin
by the glacier of Aletsch. There are erratics some two or three
hundred feet above this great moraine, showing that the glacier
must have been more than five hundred feet thick when it left this
accumulation of loose materials at such a height. It then united,
however, with a large glacier more to the west. Its greatest
thickness, as an independent glacier, is no doubt marked, not by
the boulders lying higher up, but by the large moraine which shuts
in the lake. The direct connection of this moraine with the glacier
in its former extension is still further shown by two other
moraines, on lower levels and less perfect, but having the same
relation to the present terminus of the ice. The lower of these is
only one hundred and fifty feet above the actual level of the
glacier. These three moraines occur on the western slope of the
bay. The eastern slope is more broken, and while the rounded knolls
are quite as distinct and characteristic, the erratics are more
loosely scattered over the surface. In mineralogical character they
agree with those on the western wall of the bay. Upon the summits
of some small islands at the entrance of the bay, there are also
some remnants of terminal moraines, formed by the glacier when it
reached the main channel; that is, when it was some three miles
longer than now.
The more recent oscillations, marking the advance and retreat of
the glacier within certain limits, are shown by the successive
moraines heaped up in advance of the present terminal wall. The
central motion here, as in all the Swiss glaciers, is greater than
the lateral, the ice being pushed forward in the middle faster than
on the sides. But there would seem to be more than one axis of
progression in this broad mass of ice; for though the centre is
pushed out beyond the rest, the terminal wall does not present one
uniform curve, but forms a number of more or less projecting angles
or folds. A few feet in front of this wall is a ridge of loose
materials, stones, pebbles, and boulders, repeating exactly the
outline of the ice where it now stands; a few feet in advance of
this, again, is another ridge precisely like it; still a few feet
beyond, another; and so on, for four or five concentric zigzag
crescent-shaped moraines, followed by two others more or less
marked, till they fade into the larger morainic mass, upon which
stands the belt of wood dividing the present glacier from the bay.
Agassiz counted eight distinct moraines between the glacier and the
belt of wood, and four concentric moraines in the wood itself. It
is plain that the glacier has ploughed into the forest within some
not very remote period, for the trees along its margin are loosened
and half uprooted, though not yet altogether decayed. In the
presence of the glacier one ceases to wonder at the effects
produced by so powerful an agent. This sheet of ice, even in its
present reduced extent, is about a mile in width, several miles in
length, and at least two hundred feet in depth. Moving forward as
it does ceaselessly, and armed below with a gigantic file,
consisting of stones, pebbles, and gravel, firmly set in the ice,
who can wonder that it should grind, furrow, round, and polish the
surfaces over which it slowly drags its huge weight. At once
destroyer and fertilizer, it uproots and blights hundreds of trees
in its progress, yet feeds a forest at its feet with countless
streams; it grinds the rocks to powder in its merciless mill, and
then sends them down, a fructifying soil, to the wooded shore
below.
Agassiz would gladly have stayed longer in the neighborhood of
Glacier Bay, and have made it the central point of a more detailed
examination of the glacial phenomena in the Strait. But the
southern winter was opening, and already gave signs of its
approach. At dawn on the 26th of March, therefore, the Hassler left
her beautiful anchorage in Playa Parda Cove, six large glaciers
being in sight from her deck as she came out. The scenery during
the morning had a new scientific interest for Agassiz, because the
vessel kept along the northern side of the Strait, while the course
hitherto had been nearer the southern shore. He could thus better
compare the differences between the two walls of the Strait. The
fact that the northern wall is more evenly worn, more rounded than
the southern, had a special significance for him, as corresponding
with like facts in Switzerland, and showing that the ice-sheet had
advanced across the Strait with greater force in its ascending than
in its descending path. The north side being the strike side, the
ice would have pushed against it with greater force. Such a
difference between the two sides of any hollow or depression in the
direct path of the ice is well known in Switzerland.
Later in the day, a pause was made in Chorocua Bay, where Captain
Mayne's chart makes mention of a glacier descending into the water.
There is, indeed, a large glacier on its western side, but so
inaccessible, that any examination of it would have required days
rather than hours. No one, however, regretted the afternoon spent
here, for the bay was singularly beautiful. On either side, deep
gorges, bordered by richly-wooded cliffs and overhung by ice and
snow-fields, were cut into the mountains. Where these channels
might lead, into what dim recesses of ocean and mountain, could
only be conjectured. The bay, with all its inlets and fiords, was
still as a church. Voices and laughter seemed an intrusion, and a
louder shout came back in echoes from far-off hidden retreats. Only
the swift steamer-ducks, as they shot across, broke the glassy
surface of the water with their arrow-like wake. From this point
the Hassler crossed to Sholl Bay, and anchored at the entrance of
Smythe's Channel. As sunset faded over the snow mountains opposite
her anchorage, their white reflection lay like marble in the water.
CHAPTER 24.
1872: AGE 65.
Picnic in Sholl Bay.
Fuegians.
Smythe's Channel.
Comparison of Glacial Features with those of the Strait of Magellan.
Ancud.
Port of San Pedro.
Bay of Concepcion.
Three Weeks in Talcahuana.
Collections.
Geology.
Land Journey to Santiago.
Scenes along the Road.
Report on Glacial Features to Mr. Peirce.
Arrival at Santiago.
Election as Foreign Associate of the Institute of France.
Valparaiso.
The Galapagos.
Geological and Zoological Features.
Arrival at San Francisco.
The next day forces were divided. The vessel put out into the
Strait again for sounding and dredging, while Agassiz, with a
smaller party, landed in Sholl Bay. Here, after having made a fire
and pitched a tent in which to deposit wraps, provisions etc., the
company dispersed in various directions along the shore,
geologizing, botanizing, and collecting. Agassiz was especially
engaged in studying the structure of the beach itself. He found
that the ridge of the beach was formed by a glacial moraine, while
accumulations of boulders, banked up in morainic ridges, concentric
with one another and with the beach moraine, extended far out from
the shore like partly sunken reefs. The pebbles and boulders of
these ridges were not local, or, at least, only partially so; they
had the same geological character as those of the drift material
throughout the Strait.
The day was favorable for work, and there was little to remind one
of approaching winter. A creek of fresh water, that ran out upon
one part of the beach, led up to a romantic brook, rushing down
through a gorge bordered by moss-grown trees and carpeted by ferns
and lichens in all its nooks and corners. This brook took its rise
in a small lake lying some half a mile behind the beach. The
collections made along the shore in this excursion were large and
various: star-fish, volutas, sea-urchins, sea-anemones, medusae,
doris; many small fishes, also, from the tide-pools, beside a
number drawn in the seine.
Later in the day, when the party had assembled around the beach
fire for rest and refreshment, before returning to the vessel,
their lunch was interrupted by strange and unexpected guests. A
boat rounded the point of the beach, and, as it came nearer, proved
to be full of Fuegian natives, men, women, children, and dogs,
their invariable companions. The men alone landed, some six or
seven in number, and came toward the tent. Nothing could be more
coarse and repulsive than their appearance, in which the brutality
of the savage was in no way redeemed by physical strength or
manliness. They were almost naked, for the short, loose skins tied
around the neck, and hanging from the shoulders, over the back,
partly to the waist, could hardly be called clothing. With swollen
bodies, thin limbs, and stooping forms; with a childish, yet
cunning, leer on their faces, they crouched over the fire,
spreading their hands toward its genial warmth, and all shrieking
at once, "Tabac! tabac!" and "Galleta!"--biscuit. Tobacco there was
none; but the remains of the lunch, such as it was,--hard bread and
pork,--was distributed among them, and they greedily devoured it.
Then the one who, judging from a certain deference paid him by the
others, might be the chief, or leader, seated himself on a stone
and sang in a singular kind of monotonous, chanting tone. The
words, as interpreted by the gestures and expressions, seemed to be
an improvisation concerning the strangers they had found upon the
beach, and were evidently addressed to them. There was something
curious in the character of this Fuegian song. Rather recitative
than singing, the measure had, nevertheless, certain divisions or
pauses, as if to mark a kind of rhythm. It was brought to a close
at regularly recurring intervals, and ended always in the same way,
and on the same note, with a rising inflection of the voice. When
the song was finished, a certain surprise and expectancy in the
listeners kept them silent. This seemed to trouble the singer, who
looked round with a comical air of inquiring disappointment. Thus
reminded, the audience were quick to applaud, and then he laughed
with pleasure, imitated the clapping of the hands in an awkward
way, and nothing loth, began to sing again.
The recall gun from the Hassler brought this strange scene to a
close, and the party hastened down to the beach, closely followed
by their guests, who still clamorously demanded tobacco. Meanwhile
the women had brought the boat close to that of the Hassler at the
landing. They all began to laugh, talk, and gesticulate, and seemed
a noisy grew, chattering unceasingly, with amazing rapidity, and
all together. Their boat, with the babies and dogs to add to the
tumult, was a perfect babel of voices. They put off at once,
keeping as close as they could to the Hassler boat, and reaching
the vessel almost at the same time. They were not allowed to come
on board, but tobacco and biscuit, as well as bright calico and
beads for the women, were thrown down to them. They scrambled and
snatched fiercely, like wild animals, for whatever they could
catch. They had some idea of barter, for when they found they had
received all that they were likely to get gratuitously, they held
up bows and arrows, wicker baskets, birds, and the large
sea-urchins, which are an article of food with them. Even after the
steamer had started, they still clung to the side, praying,
shrieking, screaming, for more "tabac." When they found it a
hopeless chase, they dropped off, and began again the same chanting
recitative, waving their hands in farewell.
Always interested in the comparative study of the races, Agassiz
regretted that he had no other opportunity of observing the natives
of this region and comparing them with the Indians he had seen
elsewhere, in Brazil and in the United States. It is true that he
and his companions, when on shore, frequently came upon their
deserted camps, or single empty huts; and their canoes followed the
Hassler several times, but never when it was convenient to stop and
let them come up with the vessel. This particular set were not in a
canoe, but in a large boat of English build. Probably they had
stolen it, or had found it, perhaps, stranded on the shore. They
are usually, however, in canoes of their own making. One can only
wonder that people ingenious enough to construct canoes so well
modeled and so neatly and strongly put together, should have
invented nothing better in the way of a house than a hut built of
flexible branches, compared with which a wigwam is an elaborate
dwelling. These huts are hood-like in shape, and too low for any
posture but that of squatting or lying down. In front is always a
scorched spot on the ground, where their handful of fire has
smouldered; and at one side, a large heap of empty shells, showing
that they had occupied this place until they had exhausted the
supply of mussels, on which they chiefly live. When this is the
case, they move to some other spot, gather a few branches,
reconstruct their frail shelter, and continue the same life.
Untaught by their necessities, they wander thus, naked and
homeless, in snow, mist, and rain, as they have done for ages,
asking of the land only a strip of beach and a handful of fire; and
of the ocean, shell-fish enough to save them from starvation.
The Hassler had now fairly entered upon Smythe's Channel, and was
anchored at evening (March 27th) in Otway Bay, a lake-like harbor,
broken by islands. Mount Burney, a noble, snow-covered mountain,
corresponding to Mount Sarmiento in grandeur of outline, was in
full view, but was partially veiled in mist. On the following day,
however, the weather was perfect for the sail past Sarmiento Range
and Snowy Glacier, which were in sight all day. Blue could not be
more deep and pure, nor white more spotless, than their ice and
snow-fields. Toward the latter part of the day, an immense expanse
of snow opened out a little beyond Snowy Range. It was covered with
the most curious snow hummocks, forming high cones over the whole
surface, their shadows slanting over the glittering snow in the
afternoon sunshine. They were most fantastic in shape, and some
fifty or sixty in number. At first sight, they resembled heaped-up
mounds or pyramids of snow; but as the vessel approached, one group
of them, so combined as to simulate a fortification, showed a face
of rock where the snow had been blown away, and it seemed therefore
probable that all were alike,--snow-covered pinnacles of rock.
The evening anchorage on the 28th was in Mayne's Harbor, a pretty
inlet of Owen's Island. Here the vessel was detained for
twenty-four hours by the breaking of the reversing rod. The
engineers repaired it to the best of their ability, with such
apparatus as they had, but it was a source of anxiety till a port
was reached where a new one could be supplied. The detention, had
it not been for such a cause, was welcome to the scientific party.
Agassiz found the rounded and moutonnees surfaces and the general
modeling of the outlines of ice no less marked here than in the
Strait; and in a ramble over the hills above the anchorage, M. de
Pourtales came upon very distinct glacial scorings and furrows on
dikes and ledges of greenstone and syenite. They were perfectly
regular, and could be connected by their trend from ledge to ledge,
across intervening spaces of softer decomposed rock, from which all
such surface markings had disappeared.
The country above Mayne's Harbor was pretty, though somewhat
barren. Beyond the narrow belt of woods bordering the shore, the
walking was over soggy hummocks, with little growth upon them
except moss, lichens, and coarse marsh grass. These were succeeded
by ridges of crumbling rock, between which were numerous small
lakes. The land seemed very barren of life. Even the shores of the
ponds were hardly inhabited. No song of bird or buzz of insect
broke the stillness. Rock after rock was turned over in the vain
expectation of finding living things on the damp under side at
least; and the cushions of moss were broken up in the same
fruitless chase. All was barren and lifeless. Not so on the shore,
where the collecting went on rapidly. Dredge and nets were at work
all the morning, and abundant collections were made also from the
little nooks and inlets of the beach. Agassiz found two new
jelly-fishes, and christened them at once as the locality
suggested, one for Captain Mayne, the other for Professor Owen.
Near the shore, birds also seemed more abundant. A pair of
kelp-geese and a steamer duck were brought in, and one of the
officers reported humming-birds flitting across the brook from
which the Hassler's tanks were filled.
Early on the morning of the 30th, while mountains and snow-fields,
woodland and water, still lay between moonlight and sunrise, the
Hassler started for Tarn Bay. It was a beautiful Easter Sunday,
with very little wind, and a soft sky, broken by few clouds. But
such beginnings are too apt to be delusive in this region of wet
and fog, and a heavy rain, with thick mist, came up in the
afternoon. That night, for the first time, the Hassler missed her
anchorage, and lay off the shore near an island, which afforded
some protection from the wind. A forlorn hope was detailed to the
shore, where a large fire was kept burning all night, that the
vessel might not lose her bearings and drift away. In the morning
all was right again, and she kept on her course to Rowlet Narrows.
This passage is formed by a deep gorge, cleft between lofty walls
over which many a waterfall foams from reservoirs of snow above.
Agassiz observed two old glacier beds on the western side of the
pass--two shallow depressions, lying arid and scored between
swelling wooded ridges. He had not met in all the journey a better
locality for the study of glacial effects than here. The sides of
the channel show these traces throughout their whole length. In
this same neighborhood, as a conspicuous foreground on the shore of
Indian Reach, to the south of Lackawanna Cove, is a large moraine
resembling the "horse-backs," in the State of Maine, New England.
The top was as level as a railroad embankment. The anchorage for
the night was in Eden Harbor, and for that evening, at least, it
was lovely enough to deserve its name. The whole expanse of its
land-locked waters, held between mountains and broken by islands,
was rosy and purple in the setting sun. The gates of the garden
were closed, however, not by a flaming sword, but by an
impenetrable forest, along the edge of which a scanty rim of beach
Back to Full Books
|