Scientific American Supplement, No. 799, April 25, 1891
by
Various

Part 2 out of 2



the buckets at the highest point, thus giving this wheel the greatest
possible advantage as to height of discharge for a given diameter.

[Illustration: Fig. 27.]

The power value of these wheels for raising water is a matter of
computation as nearly reliable as for other devices for the same
purpose, when the velocity of the current is known at the point of
contact with the blades.

The horse power of the wheel may be computed as for the current wheel,
Fig. 23, and, as the horse power is equal to 33,000 pounds raised one
foot high per minute, we may assume a construction of wheel that will
allow of discharging at 8 feet above the stream; then 33,000 / 8 = 4,125
pounds of water discharged at 8 feet elevation per horse power per
minute. As the net power of the wheel in the last example, for Fig. 23,
was 0.468 of a horse power, then 4,125 x 0.468 = 1,930 pounds of water
raised 8 ft. per minute by the size of bucket and velocity of current in
that case. From this a deduction of 20 per cent. should be made for loss
by spill and imperfect construction, so that 1,500 pounds or 176 gallons
per minute would be the probable output--over 253,000 gallons per day;
or, for irrigating purposes, equal to a rainfall of over 11/4 inches in
depth on 50 acres in one week.

The proportion of capacity of the lifting buckets for such a wheel
becomes of as great importance as its efficiency.

If the buckets are too large, the wheel will stall, and if too small,
the wheel will not give its full duty.

For obtaining the approximate capacity of the lifting buckets, assuming
the example as above computed, a 10 foot wheel with the velocity at
periphery of 21/2 feet per second is 150 feet per minute, or five
revolutions per minute, nearly. Then 1,930 lb. per m. / 5 revolutions =
386 pounds water capacity for all of the buckets on the wheel.

If such a wheel is constructed with 16 blades and 16 buckets, one
between each blade, then 386 / 16 = 24 pounds for each bucket, or 38 /
100 of a cubic foot.

The spill from this capacity of bucket being sufficient to compensate
for the friction of the shaft journals.

The lifting buckets of the noria class, Figs. 26 and 27, can be made of
positive dimensions to suit the computations as above; but those of the
tympanum class, Fig. 25, should be made of dimensions to conform with
the required capacity at the moment of leaving the water, as the water
at this point flows into the arm.

(_To be continued_.)

* * * * *

To remove paint and varnishes, which resist the action of strong lye,
Dr. Stockmeier recommends a mixture of water of ammonia, two parts, and
turpentine, one part; this applied to the surface to be cleaned will,
after a few minutes' action, enable the paint to be removed by use of
cotton waste or similar material.--(_Bayr. Gen. Ztg_.), Rundschau.

* * * * *




ON GAS MOTORS.


M. Witz, says the _Gas World_, has been conducting a series of
experiments on the Delamare-Deboutteville and Malindin gas engine,
driven by Dowson gas, and in which the gas generator takes the place of
the ordinary steam boiler. The engine was a one-cylinder motor in the
establishment of Messrs. Matter & Co., Rouen. Its power was 100 horse
indicated; the cylinder was 23 inches in diameter, the stroke 38 inches,
and the normal speed 100 revolutions. The engine is of the Simplex type;
the kindling is electric; the cycle of operations is fourfold, with
powerful compression. The Dowson generator is 30 inches inside diameter
and 76 inches in height from the bars to the top. Air is blown in by
steam driven in under the hearth. There is a siphon, a coke scrubber 110
inches high, a sawdust purifier, and a gasholder of 750 cubic feet
capacity, and a pipe to the engine 5.2 inches in diameter. The total
area occupied by this apparatus is 140 square yards, of which two-thirds
are built on. The anthracite employed was from Swansea, containing 5.4
per cent. of ash. The observations made with a string friction brake
were continued for 68 hours, everything used being carefully weighed and
measured. One day the machine was worked for 151/4 hours on end; the other
days it was worked with an interval of half an hour every 12 hours to
clear the hearth, poke the fire and lubricate the machine; and it was
clearly established that with a big enough generator it would be quite
possible to work continuously for several days.

The following were the data for a day of 24 hours, with an interval of
half an hour: 8:55 P.M. one day to 8:55 P.M. the next, interval 8:30 to
9 A.M. Anthracite used, 18.4 cwt.; coke used, 3.42 cwt.; water used for
steam injection, 217.3 gallons; water used in scrubber, 4,106 gallons;
water used in cooling the cylinder, 20,000 gallons; oil used in
cylinder, 14.84 pounds; grease, 1.8 pounds; revolutions of machine,
142,157, or 100.8 per minute; effective work, 75.86 French horse power,
or 77.4 British; gas used, 6,742 cubic feet per hour, at 772 mm.
pressure and 70.7 deg. F., or 83.7 cubic feet per effective horse power;
efficiency, 69 per cent.

Now, with regard to the comparison between the large gas motors and
steam engines of the same size, M. Witz goes on to remark that the gas
engine is by no means, as was formerly thought on high authority,
necessarily restricted to the domain of smaller work and sizes. Even in
early times it was seen that the gas engine belonged to a type in which
there were possibilities of improvement greater than those available in
the steam engine, because the difference of temperature between the
working substance in its hotter and its cooler condition was greater
than in the steam engine; and consumptions of 5,250 cubic feet per horse
power per hour soon descended step by step as far as 2,060, while the
power went up, past 4, 8 and 12, to 25 or 50 horse power; and in the
exhibition of 1889 there were gas engines seen in which the explosion
chamber had a diameter of as much as 23 inches.

But the price of coal gas seemed to be too high for use in these large
engines, in which sizes steam is comparatively cheap; and so poorer gas,
which, though possessing only about 28 per cent. of the heating power,
is still cheaper in proportion than coal gas, when it is made on the
spot, was introduced to tide over the difficulty. Difficulties have been
successively overcome, with the result which we have just seen, namely,
1.37 pounds of anthracite per effective horse power, or about half the
carbon which a steam engine of the same power of excellent design, and
well kept up, would consume. A 50 horse simplex at Marseilles, in
Barataud's flour mill, is said to have run for the last 2 years on 1.12
pounds of English anthracite per effective horse power; and thus M. Witz
says his predictions of 10 years ago, that the gas producer would some
day replace the boiler, are being verified in such a way as to surprise
even himself.

But the objection is stated, and it is a serious one: the weight of fuel
is not the only thing to be considered. The steam engine uses coal, the
producer requires English anthracite, which is dearer; the gas motor
uses a great deal of water and a great deal of oil, which cost money;
and gas motors are dear, while gas producers and their adjuncts cost a
tidy bit of money, and wear out pretty fast. Is not steam, after all,
more economical in the long run? Besides, producers are bulky and take
up a great deal of space; the weight of fuel is only one element in a
complicated problem.

In order to study the grounds of this objection, M. Witz has instituted
a comparison between the actual cost of large steam engines and that of
gas motors of similar size.

Take a good Galloway or multitubular boiler; for 75 horse power
effective the heating surface must be at least 74 square feet. Using
good Cardiff coal, with 4 per cent. of ash, and a heating power of
15,660 Fahr. units; the steam raised will be 8 to 9 pounds per pound of
coal, so that 9,400 to 10,577 Fahr. units are utilized in raising steam,
or 68 to 76 per cent., which is an excellent result. Take an engine of
16 inch cylinder diameter, 40 inch stroke, and 66 revolutions, etc.; it
will use 22.4 pounds of steam per horse power effective, which
represents 2.47 to 2.8 pounds of coal under the boiler. These 10 pounds
of steam carry 11,752 Fahr. units of heat, and produce work equal to 75
horse, or 1,143 Fahr. units of heat; which corresponds to an efficiency
of 9.7 per cent. In a gas motor, on the other hand, we find the
materials employed, as per the above data, to contain 8,958 Fahr. units
of heat, and to make gaseous fuel in which 6,343 units are available; a
return of 70.6 per cent, in the producer. The motor receives these
6,343, and converts 1,143 of them into work; an efficiency of 18 per
cent. In order to be equivalent from the heat point of view, a steam
engine ought to produce a horse power effective per 9.72 pounds of steam
at 5 atmospheres; but no such steam engine exists.

M. Witz goes on with comparative estimates. For a Corliss engine and
boiler, with chimney, etc., complete, and putting these up, he allows
L1,280; for a Simplex gas motor and Dowson producer complete, including
putting up, he allows L1,290, which he explains to be average actual
prices; but these prices do not cover cost of transport, and M. Witz
does not go into cost of masonry for buildings, apart from foundations,
etc., for the apparatus and machinery.

As to water, the gas motor takes 215 cubic feet per horse power
effective. A condensing steam engine uses five times as much.

The lubricating oil used at Rouen was a mixture of Russian oil at 430
fr. per ton, and Ferry and Heduit F.H. oil at 900 fr.; the average was
650 fr. per ton, or 2.8d. per pound. Wanner grease, at 6.4d. per pound,
was used for the moving parts. A steam engine requires less oil for the
cylinder, but the same quantity for the moving parts.

The attendance on the gas motor is too much for one man, not enough to
occupy two; reckon it at 4s. 91/2d. a day.

These elements enable us to calculate the daily cost of the gas motor,
of 75 actual horse power, in comparison with a steam engine of the same
size.

_Steam Engine_.

s. d.
Upkeep, interest and sinking fund at 15 per
cent, on L1,292 = L193.8 = per day. 12 11
Cardiff coal, 2.643 pounds per actual horse
power per hour; 2.643 x 10 x 75 = in 10
hours 1,982 pounds coal at 22s. a ton. 19 51/2
Oil, 3.36 pounds per day at 2.8d. per pound. 0 91/2
Grease, 0.67 pound at 6.4d. 0 41/2
Wages. 4 91/2
---------
L1 18 4

_Gas Engine_.

s. d.
Upkeep, interest and sinking fund at 15 per
cent. on L1,292 is, per day. 12 11
Anthracite, 1.156 pound per actual horse
power per hour = for 750 horse-hours, at
25s. 6d. 9 10
Coke, 0.215 pound x 10 x 75 = 1611/4 pounds
at 28s. 2 0
Oil, 0.0084 pound per actual horse power per
hour, or 0.0084 x 10 x 75 = 6.28 pounds at
2.8d. 1 51/2
Grease, 0.754 pound per day at 6.4d. 0 5
Electric kindling, on cost. 0 31/2
Wages. 4 91/2
---------
L1 11 8

The big gas engine making its own poor gas, and running 10 hours a day,
has thus the best of it in the comparison with the steam engine of equal
power.

* * * * *




A PROJECTING APPARATUS FOR BALANCES OF PRECISION.


The luminous projection apparatus illustrated herewith, when adapted to
a balance of precision, permits of effecting weighings very rapidly. For
the same approximation, the velocity of oscillation becomes five or six
times greater, and, by the method employed, the last centigrammes and
the milligrammes and their fractions are estimated directly, with
immediate verification. As the apparatus is independent of the parts of
the balance, it can be placed on all the existing laboratory balances of
precision.

[Illustration: PROJECTING APPARATUS FOR BALANCES OF PRECISION.]

The modification introduced into the balance consists in the displacing
of the center of gravity of the beam in such a way as to diminish the
sensitiveness, and consequently to obtain a much greater velocity, and
then, by optical means, to considerably increase the amplitude of the
oscillations.

Instead of the oscillations being observed through the microscope, they
are projected upon a divided screen forming a dial, the division of
which is seen by transmitted light.

The apparatus consists of a small achromatic objective placed at the
extremity of the tube of a microscope, in which there is a divided
screen that receives the enlarged image of the reticule fixed upon the
needle. Upon this reticule are projected the rays (condensed by a
powerful lens) that come from a luminous source placed behind the
balance. The focusing is done by means of a rack and pinion.

The luminous source employed is a gas burner with reflector. This is
placed in a walnut box in order to prevent any projection of heat upon
the balance. This burner, thus isolated, is lighted for but one or two
minutes at a maximum, at the end of each weighing. So, on fixing a
thermometer in the cage, we find that no variation, ever so slight,
occurs in the temperature. In order to effect a weighing, the gas being
turned down to a taper, we proceed as with an ordinary balance until the
extremity of the needle no longer emerges from the lower dial. Then we
count the difference of the number of the divisions made by the needle
to the right and left of zero. This difference, multiplied by the
approximate value, in milligrammes, of each division of this dial (value
given by the instrument) immediately gives the number of centigrammes
and milligrammes that must be added to the weights already placed upon
the pan of the balance in order to obtain an equilibrium, to about a
half division of the lower dial.

The value of each division of this dial varies from 3 to 10 milligrammes
according as the balance shows 0.1 or 0.5 milligramme. As the dial has
10 divisions on each side of the central mark, we thus estimate, without
tentatives, the three last centigrammes or the last decigramme,
according to the sensitiveness.

At this moment the doors of the cage are closed, in order to prevent
draughts of air, the gas is turned on by means of a regulating cock, and
the balance is manipulated by first lowering the beam and then bringing
the pans to a standstill. We then read the difference of the divisions
traversed to the left and right upon the luminous dial through the image
of the reticule. The images are reversed upon the dial, but practice
soon causes this petty difficulty to disappear. This number of divisions
indicates the number of milligrammes and fractions of a milligramme by
which it is necessary to shift the counterpoise on its arm in order to
obtain a perfect equilibrium, which latter is verified by a simple
reading. Every half division of the dial corresponds, as to weight, to
the sensitiveness indicated for the instrument.

With a little practice a weighing effected as above described takes but
a quarter or a fifth of the time that it does with an ordinary
balance.--_Revue Industrielle._

* * * * *




STARCHES FOR THE FINISHING OF COTTON FABRICS.


The starches have been classified by Dr. Muter, according to the
appearance they give under the microscope, into five groups:

_Class I_.--Hilum and concentric rings visible. All the granules, oval
or ovate. Tous-le-mois, potato, arrowroot, etc.

_Class II_.--The concentric rings are all but invisible, the hilum is
stellate. Maize, pea, bean, etc.

_Class III_.--The concentric rings are all but invisible, also the hilum
in the majority of granules. Wheat, barley, rye, chestnut, etc.

_Class IV_.--All the granules truncated at one end. Sago, tapioca, etc.

_Class V_.--All the granules angular in form. Rice, tacca, arrowroot,
oats, etc.

The principal starches used for finishing cotton fabrics are potato
(farina), wheat, Indian corn (maize), rice, tapioca, arrowroot, sago;
the last three not so often as those previously named.

[Illustration: POTATO STARCH.]

[Illustration: ARROWROOT STARCH.]

[Illustration: WHEAT STARCH]

[Illustration: RICE STARCH]

[Illustration: SAGO STARCH]

[Illustration: INDIAN CORN STARCH]

[Illustration: TAPIOCA STARCH]

* * * * *




MARBLE AND MOSAIC.

[Footnote: A paper recently read before the Architectural Association,
London.--_From the Architect_.]

By T.R. SPENCE.


I do not propose to enter into any historical details as to the first
and subsequent application of mosaics. In a general sense we understand
mosaic as a combination of various more or less imperishable
materials--fixed together by cement or other adhesive substances--and
laid over walls, floors, etc., with a view to permanent decorative
effect. The substance of the tesserae is of many kinds, namely, glass,
cheap and precious marbles, hard stone, and burnt clay, these mentioned
being mainly in use for architectural purposes. For decorative schemes
we collect as many gradations of color as are obtainable in such durable
materials in their natural or manufactured state, and thus form a color
palette which we regard in the same sense as a painter would his
pigments.

Of course, the first proceeding is to prepare a design on a small scale,
which shall embrace your notions of color only. Then follows a
full-sized cartoon, which I need hardly add shall embrace your best
efforts in drawing. A tracing is made of the latter and transferred to
sheets of cardboard. This cardboard is cut to the size of certain
sections of your design, and, for convenience, should not be more than,
say, 20 in. square. Of course, it will not always be square, but will
bear the same relation to your complete cartoon as a map of the counties
would to that of all England. Now, working from the small design (of
color), the tesserae are cut to the forms required, laid face downward,
and glued on to the cardboard sections containing your enlarged cartoon.
When the design is all worked out on these sections they are ready for
fixing on walls or floor by laying them home on a float of cement. When
the cement sets, the cardboard sticking to the face is washed off, and
the joints of tesserae flushed over with cement and cleaned off, leaving
all joints filled up level.

There are other processes used for the same end. The technical processes
need not occupy our attention at present. There is one process that may
appeal to you, and that is executing the work _in situ_ by floating on a
limited expanse of cement, and sticking on the tesserae at once. It has
the advantage of enabling the artist or architect to see the effect of
his efforts under the fixed conditions of light and height.

I shall confine myself to vitreous or glass mosaic, which for
durability, extended scales of primary colors and their numerous
semi-transparent gradations is unequaled by any substance yet used for
wall or floor decoration. I am surprised, having all these fine
qualities, it is not more used by architects. If you require proofs of
its triumphs, go to St. Mark's, of Venice, and stand under its mellow
golden roof. There you will find its domes and vaulted aisles, nave and
transepts entirely overlaid with gold mosaic, into which ground is
worked--in the deepest and richest colors and their gradations that
contemporary manufacturers could produce--subjects selected from the
creation down to the life of Christ, in addition containing a complete
alphabet of early Christian symbolism. The roof surfaces being one
succession of over-arching curves become receptive of innumerable waves
of light and broad unities of soft shadows, giving the whole an
incomparable quality of tone and low juicy color.

Never use your gold but on curved or undulating surfaces. Flat planes of
gold only give the effect of a monotonous metallic yellow, and can never
be beautiful, owing to the absence of the variations that come with
waves of shadow. By letting out the reins of imagination we might feel
that in this a tenth century Giorgione has given off the mental
impressions of all the golden autumn of his life. His material gave him
an advantage over his great followers of the fifteenth and sixteenth
centuries, insomuch that glass has a living and glowing quality of light
not existing in the somewhat clouded purity of oil or fresco.

In St. Mark's we have an example of the superb treatment in deepest and
most Titianesque scales applied to curved forms, but to find a similarly
complete example of the use of lighter tones and on flat surfaces, we
must turn to Ravenna. I can give you no adequate description of the wall
mosaics of Ravenna. In the sense of delicate color they remind me of
some of the subtile harmonies of many of the finest works of the modern
French school--of the Impressionists and others who combine that quality
with a true instinct for design. In standing before them you feel that
the Dagnan Bouverets, the Mersons, the Cazins, the Puvis de Chavannes,
etc., of the fifth century have had a hand in the conception and
realization of the beautiful compositions to be found on the nave walls
of the two churches of St. Appollinare Nuovo and St. Appollinare in
Classe. Here all the scales are of delicate degrees of light tones,
supreme in their beauty, completeness, and, most important to us, their
true decorative instinct. In the Baptistery we find what I may term a
third essay in color, by weaving in rich, dark, and glowing colors on
figures and bold sinuous forms of ornament in such a skillful and
judicious manner that the whole dome seems to be alive with harmonies,
although they are mostly primaries.

As you know, rules for the disposition of color are futile, yet some
details that struck me as eminently satisfactory may interest you. In
all cases the tesserae are of small dimensions, about a quarter of an
inch square. The stucco joints are large and open, surfaces far from
level, but undulating considerably. The tesserae stick up in parts,
brilliant edges showing. Absence of flatness gives play to the light.
The gray of the stucco joints brings the whole composition together,
serving as cool grays in a picture to give tender unity. Gold, apart
from backgrounds and large surfaces, is used very cleverly in small
pieces in borders of garments, and more especially in thin outlines to
make out the drawing and certain flowing forms of ornament. Brilliant
pieces of glass actually moulded at the kiln into forms of jewels add
brilliancy to crowns, borders, etc. These stick boldly out from the
surface. I noticed in the Baptistery below the springing of the dome a
frieze about 2 ft. 6 in. deep, having the ground entirely in black,
through which was woven in thin gold lines a delicate foliated design.
This, in conjunction with the upper surfaces in dark, rich color, had a
most delightful effect.

We, as students, can learn most from the Ravenna examples, for great are
the needs of light and silvery color in this country, where gray and
gloomy days far outnumber those in which the sun gives liberally of his
light. I may say, in passing, as our subject is really a matter of
decoration, that our nineteenth century efforts in this direction are
all of a somewhat gloomy tendency. We fill our rooms with imitations of
somber Spanish leather, stain and paint our woodwork in leathery and
muddy tones, to arrive at what is now a sort of decorator's god.
Quaintness is the name of that god. Many are the sins for which he has
to answer. Had we not better worship a deity called beauty, whose place
is a little higher up Parnassus? Why should we not in our endeavors
attempt in some measure to transfix the brilliant harmonies that follow
the sun in his liberal and gracious course? This muddy quaintness is
certainly pleasant for brief periods, when lamps are low and fire light
gilds and deepens its parts. Turn the sunlight on these so-called
triumphs of the modern decorator's art, and then you feel the lack of
many a phase of color that might have been borrowed from the thousand
and one examples that in nature he vivifies and makes brilliant.

Referring again to the Ravenna mosaics, I can only add that at the
present day an extended palette of colored glass is available. The
technical difficulties are not great, and there is no question as to the
fine qualities of design and color that are to be obtained in this
material. The great point in this, as in all other schemes of
decoration, is the art, the mental quality of conception, and the sense
of color and fitness. If we hold the precious heritage of an artist's
mind--that divine and rare something which gives form, color, and
completeness to a story, a dream or a vision--then very little
difficulty follows in making vitreous mosaic a valued servant in the
realization of a fine creation.

It is the function of architects to design suitable spaces for color
decoration, so bound in by dignified mouldings and other details of his
constructive art, in such a manner that the addition of decorative color
shall in no way mar the scheme of his complete work, but shall (under
these well ordered distributions) have set on them the seal and crown of
color which is inseparable from a perfect piece of architecture. In such
spaces he may dream his dreams, tell his stories, and stamp on them for
centuries his subtilest and divinest thoughts. May I not urge that to
such spaces must be given the best that is in you? for once placed so
shall they remain unchanged through generations, time being powerless to
add any mellow garment of tone or softening quality whatever.

I mistook the title of the subject in thinking that it was mosaic only,
and at the last moment found it was marble and mosaic. However, the same
dominant principles shall underlie the treatment of marble. It is a
question of the finer instincts for form and color.

In recent years the demand for choice decorative materials has been the
means of opening out many marble quarries all over the world. Transit
being easy, a large scale of varieties is available. One fine addition
is the Mexican onyx. My feeling is that the most beautiful marbles are
those where the soft and sinuous veins melt and die into the general
body, comparatively sharp markings dying right away at the edges into
innumerable gradations. Marbles having strong and hardly marked veins
present great difficulties in distribution. If they are near, they
offend you with their coarseness; and, placed at a distance, the hard
vein lines have very little decorative value. I should say use these in
narrow slips, with very little moulded profile or as parts of intazzio.

Mouldings should be specially designed for different marbles. I should
say mainly on the principle of sudden contrasts; that is, large members
with very little curve bound with members very small in detail, thus
obtaining sharp lines, having little surface to be influenced or
distorted by the veined markings, and serving to sharpen up and give
form to the broader members (which show the color qualities of the
marble), much as you sharpen up an ink drawing by underlining. These
small members serve the architect's purpose for the expression of
vertical and horizontal lines, and where decisive and cutting shadows
are required in the composition of his work.

If delicate carving forms part of your design, I should say statuary is
the best, as you have no veins to distort your detail. I need hardly add
that economy should be studied in using precious marbles, without
injuring the durability of the work. Contours may be built up in thin
sections.

Intazzio is a beautiful form of treating marble on an inexpensive
ground. Gem-like effects may be obtained by inlaying with smaller
pieces, following such ornamental forms as your inventive brains shall
dictate. Perhaps the pockets of your clients will be the chief dictator.

Heraldic emblazonings, inlaid in marble, are highly effective. The
conditions of the heraldry necessitate the use of many varieties, but in
such small quantities that on a large simple field they are rarely out
of harmony. In addition they map out a large and interesting variety
that will save the worry of creation of designs coming entirely from
your own brain, and you know the worry of an architect's life makes him
hail with pleasure at times a rest from the strain of creation. This
heraldic work may be seen to perfection in the chapel of the tombs of
the Medici at Florence.

At the Pitti Palace are some tables which you may know where marble
intazzio can no further go. Alabaster does not appeal to me, it is
somewhat sugary in results. If you are fortunate enough to have a
sculptor who is a sort of nineteenth century Donatello, let him work his
will on statuary or such restful marble.

The celebrated monument in the church of S. Giovanni Paulo, at Venice,
which Ruskin says is the finest monument in the world, if my
recollection serves me correctly, is in white marble, and its beauty
comes entirely from the sculptor's art. Such monuments give you much
better than any words of mine ample suggestions for marble treatment. I
may quote such names as Nicolo Pisano and Verocchio.

Photos of some of their work I have brought. Note Pisano's beautiful
white altar at Bologna, and Mina de Fiesole's work in Florence. They all
show the sculptor as supreme. Why should not we encourage individual
young sculptors more? Give them portions of your work in which they can
put all the fervor and enthusiasm of young manhood. Their powers may not
be ripe, but they possess a verve and intensity that may have forever
fled when in later years the imagination is less enthusiastic and the
pulses slower. I am sure there are many young sculptors now wanting
commissions who have been trained at the academy, and better still, in
the best French schools. I maintain that the contemporary French school
of sculpture is in its line equal to any school of sculpture that has
ever existed, not excepting that of Phidias or that of the Italian
Renaissance of the fifteenth and sixteenth centuries. I believe history
will confirm this. Why not give these men an opportunity, and help on
the movement to found a truly English school of sculpture, rather than
give all such work to trading firms of carvers, who will do you any
number of superficial feet, properly priced and scheduled, and in the
bills of quantities, of any style you please, from prehistoric to
Victorian Gothic? Of course, this is our British way of founding a great
school.

There is one method of treatment that appeals to me very strongly, and
that is the application of colored metals to marble, more especially
bronze and copper. I may quote as a successful example near the
Wellington Memorial at St. Paul's. Another suggestion--although it is
not used in combination with marble, but it nevertheless suggests what
might be done in the way of bronze panels--that is, the Fawcett
Memorial, by Gilbert, in the west chapel at Westminster Abbey.

* * * * *




THE ST. LAWRENCE HOSPITAL FOR THE INSANE.


The St. Lawrence State Hospital at Ogdensburg, N.Y., is a center of
public, professional, philanthropic, and legislative interest. Though
projected in advance of the adoption of the system of State care for the
insane, it was opened at a time to make it come under close observation
in relation to the question of State care, and the friends of this
departure from the inefficient, often almost barbarous provisions of
county house confinement could have no better example to point the
excellence of their theories than this new and progressively planned
State hospital. The members of the State Lunacy Commission and Miss
Schuyler and her colleagues of the State Charities Aid Society, who
fought the State care bills through the Legislature this winter and in
1890, would be repaid for all of their trouble by contrasting the
condition of the inmates of the St. Lawrence State Hospital with the
state they were in under their former custodians, the county officers of
the northern New York counties. At the best, even when these officials
realized the responsibility of their charge and were actuated by humane
impulses, the county houses offered no chance of remedial treatment.
Custody and maintenance, the former mainly a reliance on force, the
later often of scant provision, were the sum total of what was deemed
necessary for the lunatics. In their new environment they find
everything as different in accommodations and treatment as the word
hospital in the title of the institution is different in sound and
significance from the hope-dispelling, soul-chilling names of "asylum,"
"mad house," and "bedlam" formerly given to all retreats for the
mentally afflicted. They find, and it is an encouraging feature of the
plan that so many of them quickly see and appreciate it, that they are
considered as sufferers from disease and not from demoniacal possession.
The remarkable range of classification provided for, the adaptability of
construction to the different classifications, the reliance on
occupation, the dependence on treatment, and the subordination of the
custodial feature, except where a wise conservatism demands its
retention, are apparent alike to inmates and visitors.

This hospital is complete as to plans, and as to the power plant,
drainage, and subway construction necessary for the 1,500 patients, that
the legislature has provided for in its law establishing the
institution. Buildings are already finished and occupied that
accommodate 200 inmates, and the contractors have nearly finished part
of the central group that will bring that number up to nearly 1,300. The
appropriation asked for this year by the managers will be scaled down
considerably by Mr. McClelland, the very economical chairman of the Ways
and Means Committee of the Democratic Assembly. But, unless he has
miscalculated, there will be money enough to carry on the work of
construction to advantage for the year. An appropriation sufficient to
complete the buildings at once was thought by many to be the wisest
economy, but big figures in an appropriation bill have very little
chance this year. The bill establishing the State Hospital district and
providing for the building of the institution fixed the per capita cost
of construction, including the purchase of land, at $1,150, and the
plans have been made on that basis for 1,500 patients. But if the needs
of the district should require it, the capacity could be increased by an
almost indefinite extension of the system of outlying colony groups at a
very small per capita cost, as the central group is by far the most
expensive in construction.

The administration group in part, and one outlying group, with the
general kitchen, bakery, workshop, laundry, employes' dwelling house,
power house, and pumping station, are already erected, and have added a
feature of architectural beauty to Point Airy. This point, of itself of
picturesque and romantic beauty, juts into the St. Lawrence River at the
head of the Galoup Rapids, three miles below Ogdensburg. It is a part of
the hospital farm of 950 acres, which includes woodland, meadow, farm
land, and a market garden tract of the $100 an acre grade. The location
of the institution in these particulars and in reference to salubrity,
sewerage facilities and abundance and excellence of water supply, is
wonderfully advantageous.

In planning the hospital Dr. P.M. Wise, who has since become its medical
superintendent, aimed to take the utmost advantage of the scenic and
hygienic capabilities of the site, and to improve on all previous
combinations of the two general divisions of a mixed asylum--a hospital
department for the concentration of professional treatment, and a
maintenance department for the separate care of the chronic insane. He
was anxious to secure as much as possible of the compactness and ease of
administration of the linear plan of construction, with wings on either
side of the executive building of long corridors occupied as day rooms,
with sleeping rooms opening out of them on both sides. But he wanted to
avoid the depressing influence of this monotonous structure, as the
better results of variety and increased opportunities of subdivision and
classification are well recognized. He was not, however, prepared to
accept wholly that abrupt departure from the linear plan known as the
"cottage plan," which in some institutions has been carried to the
extreme of erecting a detached building for every ward. The climate of
St. Lawrence county forbade this. Her winters are as vigorous as those
of her Canadian neighbors, even as her people are almost as ebullient in
their politics as the vigorous warring liberals and conservatives across
the river. And there are features of the linear plan that can only be
left out of our asylum structure at the expense of efficiency. Other
rules that he formulated from his experience were that a building for
the insane should never exceed two stories in height; that fire proof
construction and at least two stairways from the upper floors should be
provided; that day rooms should be on the first and sleeping rooms on
the second floor; that all buildings for the insane who suffer from
sluggish and enfeebled circulation of the blood should be capable of
being warmed to 70 deg. in the coldest weather; that ample cubic space and
ventilation should be provided; and that, as far as possible, without
too great increase of the cost of maintenance or sacrificing essential
provisions for treatment and necessary restraint, asylums should aim to
reproduce the conditions of domestic life.

[Illustration: THE ST. LAWRENCE HOSPITAL FOR THE INSANE.]

State Architect Isaac G. Perry planned the St. Lawrence State Hospital
buildings on ideas suggested by medical experience, with a breadth of
comprehension and a technical skill in combining adaptability, utility,
and beauty that have accomplished wonders. The buildings are
satisfactory in every particular to every one who has seen them, and
even the most casual observer is impressed with the effect of beauty.
This was accomplished without elaboration of material, expressive
carving or finish. The ornamentation is purely structural and is
obtained by a handling of the materials of construction which also
yielded the largest promise of strength and durability.

The central hospital group, of which an idea is given in the cut, now
consists of five buildings. The picture shows three, the center one and
two of the flanking cottages on one side. They are matched on the other
side. The central or administration building is a three story structure
of Gouverneur marble, and, like all of the stone used, a native St.
Lawrence county stone. The marble's bluish gray is relieved by sparkling
crystallizations, and its unwrought blocks are handled with an
ornamental effect in the piers, lintels, and arches, and well set off by
a simple high-pitched slate roof, with terra-cotta hiprolls, crestings,
and finials. The open porches are both ornamental and useful, taking the
place of piazzas. The tower is embellished with a terra-cotta frieze.
All accommodations for an executive staff for the 1,500 patients may be
provided in this building.

Behind it on the south is a one story building whose ground plan is the
segment of a circle. It contains sun rooms, medical offices, general
library, laboratory and dispensary, and the corridor connecting the
reception cottages, one for women, on one side, and one for men on the
other, with the administration building. As this one story structure is
171 feet by 41, the buildings known as cottages of the central group are
more than nominally separated. All the advantages of segregation and
congregation are combined.

The reception cottages are of pale red Potsdam sandstone. Their simple
construction is pleasing. The ground plan is in the form of a cross; the
angles of the projections being flanked by heavy piers between which are
recessed circular bays carried up to the attic and arched over in the
gables. The cross plan affords abundant light to all the rooms, and as
much of the irregular outline as possible is utilized with piazzas. With
still another recourse to the combination corridor plan, the observation
cottages are joined to the reception cottages on each side. The other
utilization of the corridor in this case is for conservatories. The
observation cottages are irregular in plan and vary from each other and
from the other buildings in the group. Unwrought native bluestone is the
building material. These cottages contain a preponderance of single
rooms, the purpose being to keep patients separate until their
classification is decided upon.

The buildings planned but not yet constructed of the central group
include two cottages for convalescents and two one-story retreats for
noisy and disturbed patients. In both cases the plans are the most
complete and progressive ever made. In the first the degree of
construction is reduced to the minimum. Convalescents are to have
freedom from the irritations of hospital life that often retard
recovery. Great reliance is placed upon that important element in
treatment, the rousing of a hopeful feeling in the mind of the patient.

The retreat wards, with accommodations in each wing for eighteen
patients, show in this particular how little the old method of strict
confinement is to be employed in the new institution. That proportion of
the total insane population of 1,500 is regarded as all that it is
necessary to sequester to prevent the disturbance of the rest. Hollow
walls, sleeping room windows opening into small areas, and corridor
space between the several divisions are features which make the per
capita cost of the construction comparatively large for these two
cottages, but which, it is believed, will prove to be wise ones.

All of these buildings are as complete from a hospital standpoint as can
possibly be devised. Outer walls wind and moisture proof, and inner
walls of brick, with an absolutely protected air space between, insure
strength and warmth. An interior wall finish of the hardest and most
non-absorbent materials known for such uses is a valuable hygienic
provision, and both safety and salubrity are further conserved by an
absence of any hollow spaces between floors and ceilings, or in stud
partitions. No vermin retreats, no harbors for rodents, no channels for
flame exist. Heating is accomplished by indirect radiation with the
steam supply from the power house, but there are many open fireplaces to
add to the complete stack and flue system of ventilation.

Attached to the central group and completed are the kitchen building,
the laundry building and a dwelling house for employes, which are so
disposed in the rear of the group as to make a courtyard of value for
the resort of patients, as the main buildings protect and shelter it.
These buildings are ample for their work when the institution's full
capacity is attained. The kitchen building is a particularly interesting
one. All of the cooking is to be done there, and a system of subways,
with tracks on which food cars are run, connects it with all of the
groups. An idea of the magnitude of kitchen plans for such an
institution may be got from one single fact. The pantry is a lofty room,
20x32 feet.

The calculation that 80 per cent. of the insane of the district would be
in the chronic stages of the disease explains the provision in detached
cottage groups for this proportion of the patients. A great proportion
of these are feeble and helpless, requiring constant attendance night
and day, but attendance that can be given cheaply and efficiently in
associate day rooms, dining rooms and large dormitories. Detached group
No. 1, which is completed, is an infirmary group for patients of both
sexes of this class. It is chiefly one story in height, and the plan
permits an abundance of sunlight and air for every room.

Detached group No. 2 is intended for 185 men of the chronic insane
class, who require more than ordinary care and observation. Detached
group No. 3 is composed of two-story buildings for 322 women. It has
several large work-shops. Occupation is one of the main reliances of the
planners of the institution as a part of the treatment there.

Detached group No. 4 is designed for both men and women, and will
accommodate 150. A wholly different classification is here provided for,
the actively industrious classes being intended for this group. Those
who are able to do outdoor work, and for whom some diverting employment
will be beneficial in making them contented and physically healthy, will
live here. There is complete separation of day rooms, but the two sexes
will dine together in an associate hall.

An amusement hall to harmonize with the central group, and to be built
adjacent to it, is planned, and will be built this year if the
appropriation will permit. It is a valuable and necessary adjunct to the
other provisions for the care of a population of 1,500. Accommodations
for entertainments, chapel exercises, dancing and a bathing
establishment are included in the plans in a way that gives great
results with great economy of construction.

Probably the feature in the scheme of the St. Lawrence State Hospital of
the greatest popular and professional interest is Dr. Wise's plan to
have there an Americanized and improved Gheel. The original Gheel in
Belgium is a colony where for many years lunatics have been sent for
domiciliary care. Its inhabitants, mostly of the peasant class, have
grown accustomed to the presence and care of patients with disordered
minds. The system is the outgrowth of a superstition founded in the
presumed miraculous cure of a lunatic whose reason was restored by the
shock of the sight of the killing of a beautiful girl by her pursuing
father, whose fury had been roused by her choice of a husband. A
monument to this unfortunate graces Gheel, and as St. Dymphna she is
supposed to be in benign control of the lunatic-sheltering colony. Some
of the features of the Gheel system of care are also distinctively known
as the Scotch system. There the placing of patients in family care is
common. Massachusetts has also adopted it to a considerable extent. But
there are many objections to family care in isolated domiciles, as
practiced in Massachusetts. Special medical attention and official
visits are made expensive and inconvenient. Dr. Wise plans to get all
the advantages of such a mode of life for patients whose condition
retrogrades under institutional influence. Not the least of these
advantages is that of economy in relieving the State from the per capita
cost of construction for at least one-fourth of the insane of the
district. He would utilize the families in the settlement which always
grows up in the vicinity of a large hospital. It is composed of the
households of employes, many of which are the result of marriages among
the attendants and employes. On Point Airy, by the use of the buildings
that were on the different plots bought by the State to make up the
hospital farm, such a settlement can be easily made up. Its inhabitants
would pay rent to the State. They would be particularly fit and proper
persons to board and care for patients whose condition was suitable for
that sort of a life, and the patients could have many privileges and
benefits not possible in the hospital. Point Airy's little Gheel on such
a plan would be a most interesting and valuable extension of the
beneficent rule of St. Dymphna.

The St. Lawrence State Hospital was built and is operated under the
supervision of a board of managers, whose fidelity to it is described as
phenomenal by the people of Ogdensburg. The members of the executive
committee, Chairman William L. Proctor, Secretary A.E. Smith, John
Hannan and George Hall, especially Mr. Proctor and Mr. Smith, have given
as much time and attention to it as most men would to a matter in which
they had a business interest. The result has been a performance of
contract obligations in which the State got its money's worth. The
people of Ogdensburg, too, have taken a great interest in the
institution. Such men as Mayor Edgar A. Newell, ex-Collector of the Port
of New York Daniel Magone, Postmaster A.A. Smith, Assemblyman George R.
Malby, and his predecessor, Gen. N.M. Curtis, who was the legislative
father of the hospital scheme; Frank Tallman and Amasa Thornton take as
much pride in the institution that the State has set down at the gates
of their city as they do in their cherished and admired city hall, which
combines a tidy little opera house with the quarters necessary for all
public and department uses.

The executive staff of the hospital consists of Dr. P.M. Wise, medical
superintendent; Dr. J. Montgomery Mosher, assistant: Dr. J.A. Barnette
and Steward W.C. Hall.--_N.Y. Sun_.

* * * * *




THE ELECTRICAL PURIFICATION OF SEWAGE AND CONTAMINATED WATER.

[Footnote: Recently read before the Chemical Society, London. From the
_Journal_ of the Society.]

By WM. WEBSTER.


The term sewage many years ago was rightly applied to the excremental
refuse of towns, but it is a most difficult matter to define the liquid
that teems into our rivers under the name of sewage to-day; in most
towns "chemical refuse" is the best name for the complex fluid running
from the sewers.

It is now more than ten years since I first commenced a series of
experiments with a view of thoroughly testing various methods of
purifying sewage and water contaminated with putrefying organic matter.
It was while investigating the action of iron salts upon organic matter
in solution and splitting up the chlorides present by means of
electrolysis, that I first became aware of the importance of
precipitating the soluble organic matter in such manner that no chemical
solution should take the place of the precipitated organic matter. If
chemical matter is substituted for the organic compounds, the cure is
worse than the disease, as the resulting solution in most cases sets up
after precipitation in the river into which it flows.

My first electrolytical experiments were conducted with non-oxidizable
plates of platinum and carbon, but the cost of the first and the
impossibility of obtaining carbon plates that would stand long-continued
action of nascent chlorine and oxygen made it desirable that some
modification should be tried. I next tried the effect of electrolytic
action when iron salts were present, but did not think of using iron
electrodes until after trying aluminum. I found that the action of
non-oxidizable electrodes was most efficacious after the temperature of
the fluid acted upon rose 4 deg. or 5 deg.; but the cost of working made it
impossible on a large scale.

After a long series of experiments, iron plates were used as electrodes,
with remarkable results, for the compounds of iron formed not only
deodorized the samples of sewage acted on, but produced complete
precipitation of the matters in suspension, and also of the soluble
organic matter; the resulting effluents remaining perfectly free from
putrefaction. The first part of the process is well illustrated by the
small experiments now shown; the organic matter in suspension and in
solution separates into flocculent particles, which rise to the top of
the liquid and remain until the bubbles of hydrogen which have carried
them up escape, when the solid matter will precipitate. In the
arrangement adopted on a working scale, the separated particles
precipitate readily. As an illustration of the action upon organic
matter in solution I take a small quantity of dye, mix it with water,
and placing the connected iron electrodes in the mixture, the dye in
solution separates into flocculent particles. The electrolytical action
is of course easily understood, but the chemical changes that take place
need an explanation. At the positive pole, hypochlorite of iron seems to
be formed at first, but this is quickly changed into a protochloride,
and as at the negative pole an alkaline reaction takes place, the iron
salt is precipitated in the form of the ferrous hydrated oxide, together
with the organic matters in suspension and solution. Owing to the
carbonates that are always present in sewage, ferrous carbonate is also
formed.

The success of these laboratory experiments led me to a trial of the
process on a larger scale, for hitherto only a gallon at any one time
had been treated.

Small brick tanks were erected at my wharf at Peckham and iron
electrodes fitted to them.

Wrought iron plates were fixed about an inch apart, and connected in
parallel in the tanks, forming one big cell. Sewage to the amount of
about 200 gallons was run into the electrode tank and then treated, the
results being so satisfactory that larger works were erected, when a
supply of sewage equal to 20,000 gallons an hour could be obtained.

After a number of experiments had been carried out it was decided to run
the sewage as rapidly as possible through electrodes, six cells or two
rows in series fixed in a long channel or shoot, for experience showed
that the motion of the liquid acted on reduced the back E.M.F. and
hastened the formation of the precipitate.

A channel is kept at the bottom of the electrodes for the silt to
collect, with a culvert at side to flush it into, so as to prevent any
block occurring; the advantage of this is obvious. The plates in each
section may be from half an inch to an inch thick, and can be of any
length up to 6 ft. It may possibly be objected that a large number of
plates is required. This may be so, but the larger the number of plates,
the less the engine power required, and the longer they last. In each
section the electrodes are in parallel, and any one section is in series
with the other, the arrangement being exactly like that of a series of
primary battery cells.

By actual experience I have been able to prove that at least 25 sections
of electrodes should be in series and across any one of these sections
the potential difference need not be greater than 1.8 volts, the current
being of any desired amount, according to the surface of plates used.

The electrical measurements taken by Dr. John Hopkinson during these
experiments for the Electrical Purification Association, to whom I had
sold my patents, entirely corroborated my contentions as to E.H.P. used,
and agreed with the measurements of the managing electrician, Mr.
Octavius March.

The process was then thoroughly investigated by Sir Henry Roscoe, who
had control of the works for one month. He reports as follows:

"The reduction of organic matter in solution is the crucial test of the
value of a purifying agent, for unless the organic matter is reduced,
the effluent will putrefy and rapidly become offensive.

"I have not observed in any of the unfiltered effluents from this
process which I have examined any signs of putrefaction, but, on the
contrary, a tendency to oxidize. The absence of sulphureted hydrogen in
samples of unfiltered effluent, which have been kept for about six weeks
in stoppered bottles, is also a fact of importance. The settled sewage
was not in this condition, as it rapidly underwent putrefaction, even in
contact with air, in two or three days.

"The results of this chemical investigation show that the chief
advantages of this system of putrefaction are:

"First.--The active agent, hydrated ferrous oxide, is prepared within
the sewage itself as a flocculent precipitate. (It is scarcely necessary
to add that the inorganic salts in solution are not increased, as in the
case where chemicals in solution are added to the sewage.) Not only does
it act as a mechanical precipitant, but it possesses the property of
combining chemically with some of the soluble organic matter and
carrying it down in an insoluble form.

"Second.--Hydrated ferrous oxide is a deodorizer.

"Third.--By this process the soluble organic matter is reduced to a
condition favorable to the further and complete purification by natural
agencies.

"Fourth.--The effluent is not liable to secondary putrefaction."

Mr. Alfred E. Fletcher also investigated the process subsequently, and
reports as follows:

"The treatment causes a reduction in the oxidizable matter in the
sewage, varying from 60 to 80 per cent. The practical result of the
process is a very rapid and complete clarification of the sewage, which
enables the sludge to separate freely.

"It was noticed that while the raw sewage filters very slowly, so that
500 c.c. required 96 hours to pass through a paper filter, the
electrically treated sewage settled well and filtered rapidly.

"Samples of the raw sewage, having but little smell when fresh, stank
strongly on the third day. The treated samples, however, had no smell
originally, and remain sweet, without putrefactive change.

"In producing this result two agencies are at work, there is the action
of electrolysis and the formation of a hydrated oxide of iron. It is not
possible, perhaps, to define the exact action, but as the formation of
an iron oxide is part of it, it seemed desirable to ascertain whether
the simple addition of a salt of iron with lime sufficient to neutralize
the acid of the salt would produce results similar to those attained by
Webster's process.

"In order to make these experiments, samples of fresh raw sewage were
taken at Crossness at intervals of one hour during the day. As much as
10 grains of different salts of iron were added per gallon, plus 15.7
grains of lime in some cases and 125 grains of lime in another, and the
treated sewage was allowed to settle twenty-four hours; the results
obtained were not nearly as good as the electrical method."

During the present year a very searching investigation of the merits of
various processes of sewage treatment has been made by the corporation
of Salford; among others of my electrical process. As the matter is at
present under discussion by the council, I am not in a position to give
extracts from the reports of the engineers and chemists under whose
supervision and control the work was done, but I may go so far as to say
that the results of my system of electrical treatment have proved its
efficiency and applicability to sewages of even such a foul nature as
that of Salford and Pendleton. The system was controlled continuously
for the corporation by Mr. A. Jacob, B.A., C.E., the borough engineer;
Mr. J. Carter Bell, F.I.C., etc., county analyst; Messrs John Newton &
Sons, engineers, Manchester; Mr. Giles, of Messrs. Mather & Pratt,
electrical engineers, Manchester; Dr. Charles A. Burghardt, lecturer in
mineralogy at Owens College.

I would also refer you to a paper recently read before the Manchester
Section of this Society by Mr Carter Bell, the borough analyst for
Salford, in whose remarks Dr. Burghardt, an independent authority,
permits me to add that he concurs. He cannot give details until his
report has gone in, which will be very shortly.

Mr. Carter Bell's report _has_ gone in, and although he is precluded
also from giving full details, he has kindly put at my disposal samples
sealed by him of the effluents produced by the electrical treatment,
which I now submit, together with the analyses in the table.

The samples are taken at random.

Whether the process will or will not be adopted by the Salford
authorities I am of course unable to say, but I think I may safely say
that the electrical process has now absolutely proved its case in regard
to the solution of the sewage problem. It is simple, efficient and, I am
sure, more economical than any other known process where duration is
taken into account.

In regard to the Salford trials it may be interesting to give the
following particulars:

______________________________________________________________________
|
| Parts in 100,000.
|________________________________________________
| | | |
| May 15. | June 7. | June 30. | July 25.
|_____________|___________|___________|__________
|Not filtered.| | |
Total solids. | 109 | 125 | 141 | 132
Loss on ignition. | 33 | 21 | 29 | 23
Chlorine. | 32 | 44 | 42 | 43
Oxygen required | | | |
for 15 minutes. | 2.56 | 0.76 | 0.27 | 0.79
Oxygen required | | | |
for three hours. | 4.27 | 0.79 | 0.50 | 1.00
Free ammonia. | 2.20 | 0.88 | 0.50 | 0.92
Albuminoid am- | | | |
monia. | 0.32 | 0.17 | 0.092 | 0.19
_____________________|_____________|___________|___________|__________

The electrical shoot was built in brick and contained 28 cells arranged
in series.

Each cell contained 13 cast iron plates 4 in. x 2 ft. 8 in. x 1/2 in.
thick connected in parallel.

The available electrode surface in each cell was 256 sq. ft.

The ampere hour treatment required for Salford was found to be about
0.37 ampere hours per gallon, and the I.H.P. per million gallons based
on these figures would be 37.

NOTE.--In estimating for the plant necessary for treating the whole of
the Salford sewage, a margin was allowed on above figures. The A.H.T.
was taken at 0.4 and the I.H.P. per million at 39 to 39.5.

Mr. Octavius March, electrical engineer, who has followed the process
from the commencement, and who superintended the electrical details both
at Crossness and Salford, will give you on the blackboard a rough sketch
of the above trial plant.

The Salford tanks are admirably adapted to the application of the
electrical or in fact any process of precipitation. They are 12 in
number, and it is proposed to take two end tanks for the electrical
channels, in which the iron electrodes would be placed.

The total I.H.P. required for treating the whole of the Salford and
Pendleton sewage, taken at 10,000,000 gallons per 24 hours, is
calculated at 400 I.H.P., based on the actual work done during the
trial. The electrical plant would consist of four engines and dynamos,
any three of which could do the whole work, and three boilers, each of
200 I.H.P.

The total cost of plant, including alterations, is estimated at L16,000,
to which must be added the cost of about 5,000 tons of iron
plates--ordinary cast iron--at say L4 per ton. These plates would last
for several years.

If filtration were required, there would be an extra expenditure for
this, but it will be remarked that as the treated sewage is practically
purified when it leaves the electrical channels, these filters would be
only required for complete clarification, which for most places would
not be a necessity.

The filtering material used could be gradually prepared from the sludge
obtained after electrical treatment, unless it could be more profitably
sold as a manure, and I am not a believer in the value of sewage sludge
in large quantities. This sludge, a waste product, is converted into
_magnetic oxide of iron_, of which I have here two small samples. This
magnetic oxide is a good filtering material, but, like every other
filtering material, it would of course require renewal. There would,
however, always be a supply of the waste product--sewage sludge--on the
spot, and the spent magnetic oxide recarbonized could be used
indefinitely.

The annual cost for dealing with the Salford sewage is estimated at in
round figures L2,500 for coal, labor, maintenance of engines, boilers
and dynamos. To this must be added the consumption of iron and its
replacement, which would have to be written off capital expenditure.

If a colorless effluent were required, absolutely free from suspended
matter, the additional cost is estimated at from L1,200 to L1,500.

* * * * *




LAVENDER AND ITS VARIETIES.

By J. CH. SAWER, F.L.S.


Lavender--technically _Lavandula_. This name is generally considered to
be derived from the word _lavando_, gerund of the verb _lavare_, "to
wash" or "to bathe," and to originate from the ancient Roman custom of
perfuming baths with the flowers of this plant.

The general aspect of the various species which compose this genus of
labiate plants, although presenting very characteristic differences,
merges gradually from one species to another; all are, in their native
habitat, small ligneous undershrubs of from one to two feet in height,
with a thin bark, which detaches itself in scales; the leaves are
linear, persistent, and covered with numerous hairs, which give the
plant a hoary appearance.

The flowers, which are produced on the young shoots, approximate into
terminal simple spikes, which are, in vigorous young plants, branched at
the base and usually naked under the spikes.

As a rule, lavender is a native of the countries bordering on the great
basin of the Mediterranean--at least eight out of twelve species are
there found to be indigenous on mountain slopes.

The most commonly known species are _L. vera, L. spica_ and _L staechas_.
Commercially the _L. vera_ is the most valuable by reason of the
superior delicacy of its perfume; it is found on the sterile hills and
stony declivities at the foot of the Alps of Provence, the lower Alps of
Dauphine and Cevannes (growing in some places at an altitude of 4,500
feet above the sea level), also northward, in exposed situations, as far
as Monton, near Lyons, but not beyond the 46th degree of latitude; in
Piedmont as far as Tarantaise, and in Switzerland, in Lower Vallais,
near Nyon, in the canton of Vaud, and at Vuilly. It has been gathered
between Nice and Cosni, in the neighborhood of Limone, on the elevated
slopes of the mountains of western Liguria, and in Etruria on hills near
the sea. The _L. spica_, which is the only species besides _L. vera_
hardy in this country, was formerly considered only a variety of _L.
vera_; it is distinguished by its lower habit, much whiter color, the
leaves more congested at the base of the branches, the spikes denser and
shorter, the floral leaves lanceolate or linear, and the presence of
linear and subulate bractes.

It yields by distillation an oil termed "oil of spike," or, to
distinguish it from oil of _L. staechas_, "true oil of spike." It is
darker in color than the oil of _L. vera_, and much less grateful in
odor, reminding one of turpentine and rancid coker nut oil. It is used
by painters on porcelain, and in the manufacture of varnishes. It is
often largely admixed with essence of turpentine.

_L. Staechas_ (Stichas) was discovered prior to the year 50 A.D. in the
Staechades Islands (now the Islands of Hyeres), hence the name. At
present it is found wild in the South of Europe and North of Africa,
also at Teneriffe. The leaves are oblong linear, about half an inch long
(sometimes an inch long when cultivated), with revolute edges and
clothed with hoary tomentum on both surfaces; the spike is tetragonal,
compact, with a tuft of purple leaves at the top; the calyces are ovate
and slightly shorter than the tube of the corolla. The whole plant has a
strong aromatic and agreeable flavor. There is a variety of this species
(_L. macrostachya_) native of Corsica, Sicily, and Naples, which has
broader leaves and thicker octagonal spikes.

_L. staechas_ is known in Spain as "Romero Santo" (sacred rosemary). Its
essential oil (also that of _L. dentata_) is there obtained for
household use by suspending the fresh flowering stalks, flowers
downward, in closed bottles and exposing them for some time in the sun's
rays; a mixture of water and essential oil collects at the bottom, which
is used as a haemostatic and for cleansing wounds.

The specific gravity of Spanish oil of _L. staechas_ is 0.942 at 15 deg. C.
It boils between 180 deg. and 245 deg.. The odor of this oil is not at all
suggestive of that of lavender, but resembles more that of oil of
rosemary, possessing also the camphoraceous odor of that oil. In India
this oil is much prized as an expectorant and antispasmodic.

[Illustration: LAVANDULA VERA. LAVANDULA SPICA.

(From photographs of the plants. Natural size.)]

The other species which are distinctly characterized are _L.
pedunculata, L. viridis, L. dentata, L. heterophylla, L. pyrenaica, L.
pinnata, L. coronopifolia, L. abrotonoides, L. Lawii_, and _L.
multifida_.

The _L. multifida_ is synonymous with _L. Burmanii_. In Spain the
therapeutic properties of _L. dentata_ are alleged to be even more
marked than in the oils of any of the other species of lavender. It is
said to promote the healing of sluggish wounds, and when used in the
form of inhalation to have given good results in cases of severe
catarrh, and even in cases of diphtheria. In odor this oil strongly
suggests rosemary and camphor. Its specific gravity is 0.926 at 15 deg. C.
It distills almost completely between 170 deg. and 200 deg..

The specific gravity of the oil of _L. vera_ (according to Flueckiger and
Hanbury, _Pharmacographia_) ranges between 0.87 and 0.94. The same
authorities state that in a tube of 50 millimeters the plane of
polarization is diverted 4.2 deg. to the left.

Dr. Gladstone found (_Jnl. Ch. Soc._, xviii., 3) that a sample of pure
oil of _L. vera_, obtained from Dr. S. Piesse, indicated a specific
gravity of 0.8903 at 15 deg. C., and that its power of rotating the plane of
polarization (observed with a tube ten inches long) was -20 deg.. Compared
with these results he found the sp. gr. of oil of turpentine to be
0.8727, and the rotatory power -79 deg..

Although _L. staechas_ was well known to the ancients, no allusion
unquestionably referring to _L. vera_ has been found in the writings of
classical authors, the earliest mention of this latter plant being in
the twelfth century, by the Abbess Hildegard, who lived near
Bergen-on-the-Rhine. Under the name of _Llafant_ or _Llafantly_, it was
known to the Welsh physicians as a medicinal plant in the thirteenth
century. The best variety of _L. vera_--and there are several, although
unnamed--improved by cultivation in England, presents the appearance of
an evergreen undershrub of about two feet in height, with grayish green
linear leaves, rolled under at the edges, when young; the branches are
erect and give a bushy appearance to the plant; the flowers are borne on
a terminal spike, at the summit of along naked stalk, the spike being
composed of six to ten verticillasters, more widely separated toward the
base of the spike; in young plants two or four sub-spikes will branch
alternately in pairs from the main stalk; this indicates great vigor in
the plant, and occurs rarely after the second year of the plant's
growth. The floral leaves are rhomboidal, acuminate, and membraneous,
the upper ones being shorter than the calyces, bracteas obovate; the
calyces are bluish, nearly cylindrical, contracted toward the mouth, and
ribbed with many veins. The corolla is of a pale bluish violet, of a
deeper tint on the inner surface than the outer, tubular, two-lipped,
the upper lip with two and the lower with three lobes. Both the corolla
and calyx are covered with stellate hairs, among which are embedded
shining oil glands, to which the fragrance of the plant is due. The _L.
vera_ was identified in 1541, and introduced into England in 1568,
flourishing remarkably well under cultivation, and yielding an oil far
superior in delicacy of fragrance to that obtained from the wild plant,
or to that obtained from the same plant cultivated in any other country.

When it is remembered that north of the 50th degree of latitude the vine
yields little but garlands of leaves, and that we should attempt in vain
to cultivate the olive north of the 44th degree, it may seem strange
that the _Lavandula vera_, which is a native of about the same climate
as these, should resist, unprotected, the vigorous frosts of this
country. Even at Upsala, latitude 59 deg. 51' N., in the Botanic Garden, it
merely requires the shelter of a few branches to protect it in the
winter; but this hardiness may be accounted for by several physiological
reasons. Like all fruticulose labiates which have a hard compact tissue
and contain much oily matter, the lavender absorbs less moisture than
herbs which are soft and spongy, and, as it always prefers a dry
calcareous, even stony, soil, the northern cultivators find that by
selecting such localities the tissues of the plant take up so little
water that the frost does not injure them.

In a northern climate the length of the days in summer, and the natural
dryness of the air, compensate in some measure the reduction of
temperature, and mature the plant only to the extent sufficient for the
purpose for which it is grown. Perhaps the suspension of vital action
during winter, which must be more complete in northern latitudes, as our
frosts are more severe, tends to preserve certain plants, native of the
south, for it is observed that all plants are more sensitive to cold
when vegetation is active than when it is at rest. The vine is an
instance of this. On the other hand, when the plant is cultivated
further south than its natural boundary, the same causes seem to exert
their influence, but in the reverse sense. Lavender is cultivated on the
mountains of Yemen, in Arabia; the humidity, increasing inversely to the
latitude, compensates the exhaling force of the sun's rays, and the
elevation of the locality the effects of the heat.

Thus is confirmed, both in north and south, the law of vegetable
physiology observed by De Candolle, in the temperate climates of France,
and published in his "Essai de Geographie Botanique," that "plants can
best resist the effects of cold in a dry atmosphere, and the effects of
heat in a humid atmosphere." A mild, damp winter, like the one of
1889-1890, does more harm than a hard, seasonable frost, as the plants
are apt to make green shoots prematurely, and the late frosts nip off
these tender portions, each of which would otherwise have produced a
flower spike.

The very severe winter of 1890-1891 did not kill so many plants as the
one of 1889-1890. The stems and branches of lavender being ligneous and
strong are able to resist the force of the wind, and the plant thrives
best in a perfectly open locality, where the air circulates freely; the
oil and resin which it contains in abundance enable it to resist the
parching action of the wind and sun. Thus, on the most arid and sterile
ground on the mountain sides in the south, and especially in Spain,
plants of this genus flourish with more vigor in the season when most
other vegetation is scorched up by the ardent rays of the sun, and the
_Lavandula vera_ seems to have a predilection for such spots.

Certainly the plants then assume a more stunted appearance than in
richer soil, but at the same time the perfume is stronger and sweeter.
The calyces become charged with oil glands, and yield a greater
abundance of volatile oil.

In a very moist soil the water penetrates too much into the tissues,
detaches the bark, the plant blackens at the root, and a white fungus
attaches to the main stem and lower branches; it becomes feeble,
diseased, and dies. A rich soil furnishes too much nutriment, the plant
grows very large and herbaceous, becomes overcharged with water relative
to its assimilating and elaboratory power, especially if growing in a
cold climate, and the equilibrium of the chemical proportions necessary
for the formation of natural juices becomes deranged at the expense of
quantity and quality of the volatile oil produced.

These facts, long ago pointed out by Linnaeus, have been verified in
England. Some years ago a disease manifested itself in most of the
plantations, which, not being understood by the growers, was not
remedied (in fact, is not generally understood and remedied at the
present time), the acreage under cultivation decreased, and, partly
owing to this and a scarcity occasioned by a failure in the crop, the
price of the oil rapidly rose from 50s. to 200s. per lb. Consequently,
with the continually increasing demand and the continued rise in price,
manufacturers of lavender water and of compound perfumes in which oil of
lavender is a necessary ingredient commenced to buy the French oil, and
venders of the English oil commenced to adulterate largely the English
with the French oil.

By degrees the French oil become almost entirely substituted in England
for the English, and at present it is difficult to purchase true English
lavender water of a quality equal to that vended twenty years ago,
except at a few first class houses.

The exorbitant profits demanded by chemists and druggists, and the
incomprehensible will of the public to buy anything _cheap_, however
bad, have encouraged a marvelous increase in the figures of the imports
of French (and German, which is worse) oil.

In 1880, when the price had reached 125s. per lb., it was pointed out by
an eminent London firm that unless the cultivation in England were
extended, the price would become prohibitive, inferior oils would be
introduced into the market, and so destroy the popularity of this
beautiful perfume.

The price still rising did, in fact, induce this importation, and to
this day the bulk of chemists and perfumers continue to use these
foreign oils, notwithstanding the fall in the price of the English oil.

The constant demand, however, in America (where people will have things
good) will yet support the price of the genuine article--that is, of the
English oil, which is the finest the world produces. Attempts were made
by a French manufacturing perfumer to establish a plantation in the
south of France of plants taken from parent stems grown in England.

The result was that the young plants deteriorated to their original
condition--even there in their native habitat. The character of a plant
and the character of its produce depend even on more than a similarity
of soil and geographical position. It is asserted that a good judge can
distinguish between the oils produced by two adjacent fields, and the
difference in odor is very apparent between the oils produced in
Hertfordshire and in Surrey. The oil produced in Sussex is different
from both.--_Chemist and Druggist_.

* * * * *




SPECTRUM OF THE SUN AND ELEMENTS.


The _Johns Hopkins University Circular_, No. 85, issued in February,
contains Prof. Rowland's report of progress in spectrum work. The
spectra of all known elements, with the exception of a few gaseous ones,
or those too rare to be yet obtained, have been photographed in
connection with the solar spectrum, from the extreme ultra-violet down
to the D line, and eye observations have been made on many to the limit
of the solar spectrum. A table of standard wave lengths of the
impurities in the carbon poles extending to wave length 2,000 has been
constructed to measure wave lengths beyond the limits of the solar
spectrum. In addition to this, maps of the spectra of some of the
elements have been drawn up on a large scale, ready for publication, and
the greater part of the lines in the map of the solar spectrum have been
identified. The following rough table of the solar elements has been
constructed entirely according to Prof. Rowland's own observations,
although, of course, most of them have been given by others:

_Elements in the Sun, arranged according to Intensity and the Number of
Lines in the Solar Spectrum_.

According to intensity. According to number.

Calcium Zirconium Iron (2,000 or more) Magnesium (20 or more)
Iron Molybdenum Nickel Sodium (11)
Hydrogen Lanthanum Titanium Silicon
Sodium Niobium Manganese Strontium
Nickel Palladium Chromium Barium
Magnesium Neodymium Cobalt Aluminum (4)
Cobalt Copper Carbon (200 or more) Cadmium
Silicon Zinc Vanadium Rhodium
Aluminum Cadmium Zirconium Erbium
Titanium Cerium Cerium Zinc
Chromium Glucinum Calcium (75 or more) Copper (2)
Manganese Germanium Scandium Silver (2)
Strontium Rhodium Neodymium Glucinum (2)
Vanadium Silver Lanthanum Germanium
Barium Tin Yttrium Tin
Carbon Lead Niobium Lead (1)
Scandium Erbium Molybdenum Potassium (1)
Yttrium Potassium Palladium

_Doubtful Elements_.

Iridium, osmium, platinum, ruthenium, tantalum, thorium, tungsten,
uranium.

_Not in Solar Spectrum_.

Antimony, arsenic, bismuth, boron, nitrogen, caesium, gold, indium,
mercury, phosphorus, rubidium, selenium, sulphur, thallium,
praseodymium.

With respect to these tables, Prof. Rowland adds: "The substances under
the head of 'Not in the Solar Spectrum' are often placed there because
the elements have few strong lines or none at all in the limit of the
solar spectrum when the arc spectrum, which I have used, is employed.
Thus, boron has only two strong lines at 2497. Again, the lines of
bismuth are all compound, and so too diffuse to appear in the solar
spectrum. Indeed, some good reason generally appears for their absence
from the solar spectrum. Of course, there is but little evidence of
their absence from the sun itself; were the whole earth heated to the
temperature of the sun, its spectrum would probably resemble that of the
sun very closely."

The powerful instrument used at Baltimore for photographing spectra, and
the measuring engine constructed to fit the photographs so that its
readings give the wave lengths of lines directly within 1/100 of a
division on Angstroem's scale, give the foregoing results a weight
superior to many others published.

* * * * *




ALLOTROPIC FORMS OF METALS.


Writing on some curious properties of metals and alloys, Mr. W.C.
Roberts-Austen, says the _Engineer_, remarks that the importance of the
isomeric and allotropic states has been much neglected in the case of
metals. Joule and Lyon Playfair showed, in 1846, that metals in
different allotropic states possess different atomic volumes, and
Matthiessen, in 1860, was led to the view that in certain cases where
metals are alloyed they pass into allotropic states, probably the most
important generalization which has yet been made in connection with the
molecular constitution of alloys. Instances of allotropy in pure metals
are: Bolley's lead, which oxidizes readily in air; Schutzenberger's
copper; Fritsche' tin, which falls to powder when exposed to
exceptionally cold winter; Gore's antimony; Graham's palladium and
allotropic nickel. Joule has also proved that, when iron is released
from its amalgam by distilling away the mercury, the metallic iron takes
fire on exposure to air, and is therefore clearly different from
ordinary iron.

* * * * *




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