Scientific American Supplement, No. 384, May 12, 1883
by
Various

Part 1 out of 3







Produced by Don Kretz, Juliet Sutherland, Charles Franks and the DP Team




[Illustration]




SCIENTIFIC AMERICAN SUPPLEMENT NO. 384




NEW YORK, MAY 12, 1883

Scientific American Supplement. Vol. XV., No. 384.

Scientific American established 1845

Scientific American Supplement, $5 a year.

Scientific American and Supplement, $7 a year.


* * * * *

TABLE OF CONTENTS.

I. ENGINEERING.--Locomotive for St. Gothard Railway.--Several
figures.

The Mersey Railway Tunnel.

Dam Across the Ottawa River, and New Canal at Carillon,
Quebec. Several figures and map.

II. ARCHITECTURE.--Dwelling Houses.--Hints on building. By
WILLIAM HENNAN.--Considerations necessary in order to have-
thoroughly sweet homes.--Experiment illustrating the necessity
of damp courses.--How to make dry walls and roofs.--Methods of
heating.--Artificial lighting.--Refuse.--Cesspools.--Drainage

House at Heaton.--Illustration.

A Mansard Roof Dwelling. 2 figures.

III. ELECTRICITY.--The History of the Electric Telegraph.--Documents
relating to the magnetic telegraph.--Apparatus of Comus
and Alexandre.--Origin of the electric telegraph.--Apparatus of
Lesage, Lemond, Reveroni, Saint Cyr, and others.--Several figures.

Electrical Transmission and Storage.--By DR. C. WM. SIEMENS.

III. MEDICINE AND HYGIENE.--Malaria. By Dr. JAMES SALISBURY.--VII.
Report on the cause of ague.--Studies of ague plants
in their natural and unnatural habitats.--List of objects found in
the Croton water.--Synopsis of the families of ague plants.--
Several figures.

Ichthyol.

Autopsy Table. 1 figure.

The Exciting Properties of Oats.

Filaria Disease.

IV. CHEMISTRY.--Preparation of Hydrogen Sulphide from Coal Gas.
By J. TAYLOR. 1 figure.

Setting of Gypsum.

V. TECHNOLOGY.--On the Preparation of Gelatine Plates. By E.
HOWARD FARMER.

Pictures on Glass.

VI. NATURAL HISTORY.--Survey of the Black Canon.

The Ancient Mississippi and its Tributaries. By J. W. SPENCER.

VII. AGRICULTURE.--The Spectral Masdevallia.--Illustration.

* * * * *




LOCOMOTIVE FOR ST. GOTHARD RAILWAY.


We give engravings of one of a type of eight-coupled locomotives
constructed for service on the St. Gothard Railway by Herr T.A. Maffei,
of Munich. As will be seen from our illustrations, the engine has
outside cylinders, these being 20.48 in. in diameter, with 24 in.
stroke, and as the diameter of the coupled wheels is 3 ft. 10 in.,
the tractive force which the engine is capable of exerting amounts to
(20.48 squared x 24) / 46 = 218.4 lb. for each pound of effective pressure per
square inch on the pistons. This is an enormous tractive force, as it
would require but a mean effective pressure of 1021/2 lb. per square inch
on the pistons to exert a pull of 10 tons. Inasmuch, however, as the
engine weighs 44 tons empty and 51 tons in working order, and as all
this weight is available for adhesion, this great cylinder power can be
utilized. The cylinders are 6 ft. 10 in. apart from center to center,
and they are well secured to the frames, as shown in Fig. 4. The frames
are deep and heavy, being 1 3/8 in. thick, and they are stayed by a
substantial box framing at the smokebox end, by a cast-iron footplate at
the rear end, and by the intermediate plate stays shown. The axle box
guides are all fitted with adjusting wedges. The axle bearings are all
alike, all being 7.87 in. in diameter by 9.45 in. long. The axles are
spaced at equal distances of 4 ft. 3.1 in. apart, the total wheel base
being thus 12 ft. 9.3 in. In the case of the 1st, 2d, and 3d axles, the
springs are arranged above the axle boxes in the ordinary way, those of
the 2d and 3d axles being coupled by compensating beams. In the case of
the trailing axle, however, a special arrangement is adopted. Thus, as
will be seen on reference to the longitudinal section and plan (Figs. 1
and 2, first page), each trailing axle box receives its load through the
horizontal arm of a strong bell-crank lever, the vertical arm of which
extends downward and has its lower end coupled to the adjoining end of a
strong transverse spring which is pivoted to a pair of transverse stays
extending from frame to frame below the ash pan. This arrangement
enables the spring for the trailing axle to be kept clear of the
firebox, thus allowing the latter to extend the full width between the
frames. The trailing wheels are fitted with a brake as shown.

[Illustration: LOCOMOTIVES FOR ST. GOTHARD RAILWAY.]

The valve motion is of the Gooch or stationary link type, the radius
rods being cranked to clear the leading axle, while the eccentric rods
are bent to clear the second axle. The piston rods are extended through
the front cylinder covers and are enlarged where they enter the
crossheads, the glands at the rear ends of cylinders being made in
halves. The arrangement of the motion generally will be clearly
understood on reference to Figs. 1 and 2 without further explanation.

The boiler, which is constructed for a working pressure of 147 lb. per
square inch, is unusually large, the barrel being 60.4 in. in diameter
inside the outside rings; it is composed of plates 0.65 in. thick. The
firebox spreads considerably in width toward the top, as shown in the
section, Fig. 5, and to enable it to be got in the back plate of the
firebox casing is flanged outward, instead of inward as usual, so as to
enable it to be riveted up after the firebox is in place. The inside
firebox is of copper and its crown is stayed directly to the crown
of the casing by vertical stays, as shown, strong transverse stays
extending across the boiler just above the firebox crown to resist the
spreading action caused by the arrangement of the crown stays. The
firegrate is 6 ft. 11.6 in. long by 3 ft. 4 in. wide.

[Illustration: ST. GOTHARD LOCOMOTIVES.]

The barrel contains 225 tubes 1.97 in. in diameter outside and 13 ft. 91/2
in. long between tube plates. On the top of the barrel is a large dome
containing the regulator, as shown in Fig. 1, from which view the
arrangement of the gusset stays for the back plate of firebox casing and
for the smokebox tube plate will be seen. A grid is placed across the
smokebox just above the tubes, and provision is made, as shown in Figs.
1 and 4, for closing the top of the exhaust nozzle, and opening a
communication between the exhaust pipes and the external air when the
engine is run reversed. The chimney is 153/4 in. in diameter at its lower
end and 18.9 in. at the top. The chief proportions of the boiler are as
follows:

Sq. ft

Heating surface: Tubes 1598.5
Firebox 102.5
------
1701.0

Firegrate area 23.3 [1]
Sectional area through tubes (disregarding ferrules) 3.5
Least sectional area of chimney. 1.35
Ratio of firegrate area to heating surface. 1:73
Ratio of flue area through tubes to firegrate area. 1:6.7
Ratio of least sectional area of chimney to firegrate area. 1:17.26

[Transcribers note 1: Best guess, 2nd digit illegible]

The proportion of chimney area to grate is much smaller than in ordinary
locomotives, this proportion having no doubt been fixed upon to enable a
strong draught to be obtained with the engine running at a slow speed.
Of the general fittings of the engine we need give no description, as
their arrangement will be readily understood from our engravings, and
in conclusion we need only say that the locomotive under notice is
altogether a very interesting example of an engine designed for
specially heavy work.--_Engineering_.

* * * * *




THE MERSEY RAILWAY TUNNEL.


The work of connecting Liverpool with Birkenhead by means of a railway
tunnel is now an almost certain success. It is probable that the entire
cost of the tunnel works will amount to about half a million sterling.
The first step was taken about three years ago, when shafts were sunk
simultaneously on both sides of the Mersey. The engineers intrusted
with the plans were Messrs. Brunlees & Fox, and they have now as their
resident representative Mr. A.H. Irvine, C.E. The contractor for the
entire work is Mr. John Waddell, and his lieutenant in charge at both
sides of the river is Mr. James Prentice. The post of mechanical
engineer at the works is filled by Mr. George Ginty. Under these chiefs,
a small army of nearly 700 workmen are now employed night and day at
both sides of the river in carrying out the tunnel to completion. On
the Birkenhead side, the landward excavations have reached a point
immediately under Hamilton Square, where Mr. John Laird's statue is
placed, and here there will be an underground station, the last before
crossing the river, the length of which will be about 400 feet, with up
and down platforms. Riverward on the Cheshire side, the excavators have
tunneled to a point considerably beyond the line of the Woodside Stage;
while the Lancashire portion of the subterranean work now extends to
St. George's Church, at the top of Lord street, on the one side, and
Merseyward to upward of 90 feet beyond the quay wall, and nearly to the
deepest part of the river.

When completed, the total length of the tunnel will be three miles one
furlong, the distance from wall to wall at each side of the Mersey being
about three-quarters of a mile. The underground terminus will be about
Church street and Waterloo place, in the immediate neighborhood of the
Central Station, and the tunnel will proceed from thence, in an almost
direct line, under Lord street and James street; while on the south side
of the river it will be constructed from a junction at Union street
between the London and Northwestern and Great Western Railways, under
Chamberlain street, Green lane, the Gas Works, Borough road, across the
Haymarket and Hamilton street, and Hamilton square.

Drainage headings, not of the same size of bore as the part of the
railway tunnel which will be in actual use, but indispensable as a means
of enabling the railway to be worked, will act as reservoirs into which
the water from the main tunnel will be drained and run off to both sides
of the Mersey, where gigantic pumps of great power and draught will
bring the accumulating water to the surface of the earth, from whence
it will be run off into the river. The excavations of these drainage
headings at the present time extend about one hundred yards beyond the
main tunnel works at each side of the river. The drainage shafts are
sunk to a depth of 180 feet, and are below the lowest point of the
tunnel, which is drained into them. Each drainage shaft is supplied
with two pumping sets, consisting of four pumps, viz., two of 20 in.
diameter, and two of 30 in. diameter. These pumps are capable of
discharging from the Liverpool shafts 6,100 gallons per minute, and from
the Birkenhead 5,040 gallons per minute; and as these pumps will be
required for the permanent draining of the tunnel, they are constructed
in the most solid and substantial manner. They are worked by compound
engines made by Hathorn, Davey & Co., of Leeds, and are supplied
with six steel boilers by Daniel Adamson & Co., of Dukinfield, near
Manchester.

In addition to the above, there is in course of construction still
more powerful pumps of 40 in. diameter, which will provide against
contingencies, and prevent delay in case of a breakdown such as occurred
lately on the Liverpool side of the works. The nature of the rock is
the new red sandstone, of a solid and compact character, favorable for
tunneling, and yielding only a moderate quantity of water. The engineers
have been enabled to arrange the levels to give a minimum thickness of
25 ft. and an average thickness of 30 ft. above the crown of the tunnel.

Barges are now employed in the river for the purpose of ascertaining the
depth of the water, and the nature of the bottom of the river. It is
satisfactory to find that the rock on the Liverpool side, as the heading
is advanced under the river, contains less and less water, and this the
engineers are inclined to attribute to the thick bed of stiff bowlder
clay which overlies the rock on this side, which acts as a kind of
"overcoat" to the "under garments." The depth of the water in one part
of the river is found to be about 72 ft.; in the middle about 90 ft.;
and as there is an intermediate depth of rock of about 27 ft., the
distance is upward of 100 ft. from the surface of low water to the top
of the tunnel.

It is expected that the work will shortly be pushed forward at a much
greater speed than has hitherto been the case, for in place of the
miner's pick and shovel, which advanced at the rate of about ten yards
per week, a machine known as the Beaumont boring machine will be brought
into requisition in the course of a day or two, and it is expected to
carry on the work at the rate of fifty yards per week, so that this year
it may be possible to walk through the drainage heading from Liverpool
to Birkenhead. The main tunnel works now in progress will probably be
completed and trains running in the course of 18 months or two years.

The workmen are taken down the shaft by which the debris is hoisted, ten
feet in diameter, and when the visitor arrives at the bottom he finds
himself in quite a bright light, thanks to the Hammond electric light,
worked by the Brush machine, which is now in use in the tunnel on both
sides of the river. The depth of the pumping shaft is 170 feet, and the
shaft communicates directly with the drainage heading. This circular
heading now has been advanced about 737 yards. The heading is 7 feet in
diameter, and the amount of it under the river is upward of 200 yards on
each side. The main tunnel, which is 26 feet wide and 21 feet high, has
also made considerable progress at both the Liverpool and Birkenhead
ends. From the Liverpool side the tunnel now extends over 430 yards, and
from the opposite shore about 590 yards. This includes the underground
stations, each of which is 400 feet long, 51 feet wide, and 32 feet
high. Although the main tunnel has not made quite the same progress
between the shafts as the drainage heading, it is only about 100 yards
behind it. When completed, the tunnel will be about a mile in length
from shaft to shaft. In the course of the excavations which have been so
far carried out, about 70 cubic yards of rock have been turned out for
every yard forward.

Ten horses are employed on the Birkenhead side for drawing wagons loaded
with debris to the shaft, which, on being hoisted, is tipped into the
carts and taken for deposit to various places, some of which are about
three miles distant. The tunnel is lined throughout with very solid
brickwork, some of which is, 18 inches thick (composed of two layers
of blue and two of red brick), and toward the river this brickwork is
increased to a thickness of six rings of bricks--three blue and three
red. A layer of Portland cement of considerable thickness also gives
increased stability to the brick lining and other portions of the
tunnel, and the whole of the flooring will be bricked. There are about
22 yards of brickwork in every yard forward. The work of excavation up
to the present time has been done by blasting (tonite being employed for
this purpose), and by the use of the pick and shovel. At every 45 ft.
on alternate sides niches of 18 in. depth are placed for the safety of
platelayers. The form of the tunnel is semicircular, the arch having a
13 ft. radius, the side walls a 25 ft. radius, and the base a 40 ft.
radius.

Fortunately not a single life has up to the present time been lost in
carrying out the exceedingly elaborate and gigantic work, and this
immunity from accident is largely owing to the care and skill which are
manifested by the heads of the various departments. The Mersey Tunnel
scheme may now be looked upon as an accomplished work, and there is
little doubt its value as a commercial medium will be speedily and fully
appreciated upon completion.

* * * * *




DAM ACROSS THE OTTAWA RIVER AND NEW CANAL AT CARILLON QUE

By ANDREW BELL Resident Engineer


The natural navigation of the Ottawa River from the head of the Island
of Montreal to Ottawa City--a distance of nearly a hundred miles--is
interrupted between the villages of Carillon and Grenville which are
thirteen miles apart by three rapids, known as the Carillon, Chute a
Blondeau, and Longue Sault Rapids, which are in that order from east to
west. The Carillon Rapid is two miles long and has, or had, a fall of 10
feet the Chute a Blondeau a quarter of a mile with a fall of 4 feet and
the Longue Sault six miles and a fall of 46 feet. Between the Carillon
and Chute a Blondeau there is or was a slack water reach of three and a
half miles, and between the latter and the foot of the Longue Sault a
similar reach of one and a quarter miles.

Small canals limited in capacity to the smaller locks on them which were
only 109 feet long 19 feet wide, and 5 to 6 feet of water on the sills,
were built by the Imperial Government as a military work around each of
the rapids. They were begun in 1819 and completed about 1832. They were
transferred to the Canadian Government in 1856. They are built on the
north shore of the river, and each canal is about the length of the
rapid it surmounts.

[Illustration: THE GREAT DAM ACROSS THE OTTAWA RIVER, AT CARILLON.]

The Grenville Canal (around the Longue Sault) with seven locks, and the
Chute a Blondeau with one lock, are fed directly from Ottawa. But with
the Carillon that method was not followed as the nature of the banks
there would have in doing so, entailed an immense amount of rock
excavation--a serious matter in those days. The difficulty was overcome
by locking up at the upper or western end 13 feet and down 23 at lower
end, supplying the summit by a 'feeder from a small stream called the
North River, which empties into the Ottawa three or four miles below
Carillon, but is close to the main river opposite the canal.

In 1870-71 the Government of Canada determined to enlarge these canals
to admit of the passage of boats requiring locks 200 feet long, 45 feet
wide, and not less than 9 feet of water on the sills at the lowest
water. In the case of the Grenville Canal this was and is being done by
widening and deepening the old channel and building new locks along
side of the old ones. But to do that with the Carillon was found to be
inexpedient. The rapidly increasing traffic required more water than the
North River could supply in any case, and the clearing up of the country
to the north had materially reduced its waters in summer and fall, when
most needed. To deepen the old canal so as to enable it to take its
supply from the Ottawa would have caused the excavation of at least
1,250,000 cubic yards of rock, besides necessitating the enlargement of
the Chute a Blondeau also.

It was therefore decided to adopt a modification of the plan proposed
by Mr. T.C. Clarke, of the present firm of Clarke Reeves & Co, several
years before when he made the preliminary surveys for the then proposed
"Ottawa Ship Canal," namely to build a dam across the river in the
Carillon Rapid but of a sufficient height to drown out the Chute a
Blondeau, and also to give the required depth of water there.

During the summer and fall of 1872 the writer made the necessary surveys
of the river with that end in view. By gauging the river carefully in
high and low water, and making use of the records which had been kept by
the lock masters for twenty years back, it was found that the flow of
the river was in extreme low water 26,000 cubic feet per second, and
in highest water 190,000 cubic feet per second, in average years about
30,000 and 150,000 cubic feet respectively. The average flow in each
year would be nearly a mean between those quantities, namely, about
90,000 cubic feet per second. It was decided to locate the dam where it
is now built, namely, about the center of Carillon Rapid, and a mile
above the village of that name and to make it of a height sufficient to
raise the reach between the head of Carillon and Chute a Blondeau about
six feet, and that above the latter two feet in ordinary water. At the
site chosen the river is 1,800 feet wide, the bed is solid limestone,
and more level or flat than is generally found in such places--the banks
high enough and also composed of limestone. It was also determined to
build a slide for the passage of timber near the south shore (see map),
and to locate the new canal on the north side.

Contracts for the whole works were given out in the spring of 1873, but
as the water remained high all the summer of that year very little could
be done in it at the dam. In 1874 a large portion of the foundation,
especially in the shallow water, was put in. 1875 and 1876 proved
unfavorable and not much could be done, when the works were stopped.
They were resumed in 1879, and the dam as also the slide successfully
completed, with the exception of graveling of the dam in the fall of
1881. The water was lower that summer than it had been for thirty five
years before. The canal was completed and opened for navigation the
following spring.


THE DAM

In building such a dam as this the difficulties to be contended against
were unusually great. It was required to make it as near perfectly tight
as possible and be, of course, always submerged. Allowing for water used
by canal and slide and the leakage there should be a depth on the crest
of the dam in low water of 2.50 feet and in high of about 10 feet.
These depths turned out ultimately to be correct. The river reaches
its highest about the middle of May, and its lowest in September. It
generally begins to rise again in November. Nothing could be done except
during the short low water season, and some years nothing at all. Even
at the most favorable time the amount of water to be controlled was
large. Then the depth at the site varied in depth from 2 to 14 feet, and
at one place was as much as 23 feet. The current was at the rate of from
10 to 12 miles an hour. Therefore, failures, losses, etc., could not be
avoided, and a great deal had to be learned as the work progressed. I
am not aware that a dam of the kind was ever built, or attempted to be
built across a river having such a large flow as the Ottawa.

The method of construction was as follows. Temporary structures of
various kinds suited to position, time, etc., were first placed
immediately above the site of the dam to break the current. This was
done in sections and the permanent dam proceeded with under that
protection.

In shallow water timber sills 36 feet long and 12 inches by 12 inches
were bolted to the lock up and down stream, having their tops a uniform
height, namely, 9.30 feet below the top of dam when finished. These
sills were, where the rock was high enough, scribed immediately to it,
but if not, they were 'made up' by other timbers scribed to the rock, as
shown by Figs 4 and 5. They were generally placed in pairs about 6 feet
apart, and each alternate space left open for the passage of water, to
be closed by gates as hereafter described. Each sill was fastened by
five 11/2 in. bolts driven into pine plugs forced into holes drilled
from 18 inches to 24 inches into the rock. The temporary rock was then
removed as far as possible, to allow a free flow of the water.

In the channels of which there are three, having an aggregate width of
about 650 feet, cribs 46 feet wide up and down stream were sunk. In the
deepest water, where the rock was uneven, they covered the whole bottom
up to about five feet of the level of the silts, and on top of that
isolated cribs, 46 in. X 6 in. and of the necessary height were placed
seven feet apart, as shown at C Figs 2 and 3. At other places similar
narrow cribs were placed on the rock, as shown at D, Figs 2 and 3. The
tops of all were brought to about the same level as the before mentioned
sills. The rock bottom was cleaned by divers of all bowlders, gravel,
etc. The cribs were built in the usual manner, of 12 in. X 12 in. timber
generally hemlock, and carefully fitted to the rock on which they stand.
They were fastened to the rock by 11/2 in. bolts, five on each side of a
crib, driven into pine plugs as mentioned for the sills. The drilling
was done by long runners from their tops. The upstream side of the cribs
were sheeted with 4 in. tamarack plank.

On top of these sills and cribs there was then placed all across river a
platform from 36 to 46 feet wide made up of sawed pine timber 12 in.
X 12 in., each piece being securely bolted to its neighbor and to the
sills and cribs below. It was also at intervals bolted through to the
rock.

On top of the "platform" there was next built a flat dam of the
sectional form shown by Fig 1. It was built of 12 in. X 12 in. sawed
pine timbers securely bolted at the crossings and to the platform, and
sheeted all over with tamarack 10 in. thick and the crest covered with
1/2 in. boiler plate 3 ft. wide. The whole structure was carefully filled
with stone--field stone, or "hard head" generally being used for the
purpose.

At this stage of the works, namely, in the fall of 1881 the structure
presented somewhat the appearance of a bridge with short spans. The
whole river--fortunately low--flowed through the sluices of which there
were 113 and also through a bulkhead which had been left alongside
of the slide with a water width of 60 ft. These openings had a total
sectional area of 4,400 sq. ft., and barely allowed the river to pass,
although, of course, somewhat assisted by leakage.

[Illustration: Fig. 1. CROSS SECTION IN DEEP WATER.]

It now only remained, to complete the dam, to close the openings. This
was done in a manner that can be readily understood by reference to
the cuts. Gates had been constructed with timber 10 in. thick, bolted
together. They were hung on strong wooden hinges and, before being
closed, laid back on the face of dam as shown at B, Figs. 1, 2, and 3.
They were all closed in a short time on the afternoon of 9th November,
1881. To do this it was simply necessary to turn them over, when the
strong current through the sluices carried them into their places, as
shown at A, Figs. 2 and 3 and by the dotted lines on Fig. 1. The closing
was a delicate as well as dangerous operation, but was as successfully
done as could be expected. No accident happened further than the
displacement of two or three of the gates. The openings thus left
were afterward filled up with timber and brushwood. The large opening
alongside of the slide was filled up by a crib built above and floated
into place.

The design contemplates the filling up with stone and gravel on
up-stream side of dam about the triangular space that would be formed by
the production of the line of face of flat dam till it struck the rock.
Part of that was done from the ice last winter; the balance is being put
in this winter.

Observations last summer showed that the calculations as to the raising
of the surface of the river were correct. When the depth on the crest
was 2.50 feet, the water at the foot of the Longue Sault was found to be
25 in. higher than if no dam existed. The intention was to raise it 24
in.

The timber slide was formed by binding parallel piers about 600 feet
long up and down stream, as shown on the map, and 28 ft. apart, with a
timber bottom, the top of which at upper end is 3 ft. below the crest
of dam. It has the necessary stop logs, with machinery to move them, to
control the water. The approach is formed by detached piers, connected
by guide booms, extending about half a mile up stream. See map.

Alongside of the south side of the slide a large bulkhead was built, 69
ft. wide, with a clear waterway of 60 ft. It was furnished with stop
logs and machinery to handle them. When not further required, it was
filled up by a crib as before mentioned.

The following table shows the materials used in the dam and slide, and
the cost:

______________________________________________________________________
| | | Stone | Exca- | |
| Timber, | Iron, | filling, | vation, | Cost. |
| cu. ft. | lb. | cu. yds. | cu. yds.| |
+---------+---------+----------+---------+----------+
Temporary works | 134,500 | 92,000 | 11,400 | | $79,000 |
| | | | | |
Permanent dam | 265,000 | 439,600 | 24,000 | 6,500 | 151,000 |
| | | | | |
Slide, including | 296,500 | 156,400 | 32,800 | | 102,000 |
apparatus | | | | | |
+---------+---------+----------+---------+----------+
| | | | | |
Total | 696,000 | 687,000 | 68,200 | 6,500 | $332,000 |
-----------------+---------+---------+----------+---------+----------+

The above does not include cost of surveys, engineering, or
superintendence, which amounted to about ten per cent, of the above sum.

[Illustration: DETAILS OF THE OTTAWA RIVER DAM, AT CARILLON.]

The construction of the dam and slide was ably superintended by Horace
Merrill, Esq., late superintendent of the "Ottawa River Improvements,"
who has built nearly all the slides and other works on the Ottawa to
facilitate the passage of its immense timber productions.

The contractors were the well known firm of F.B. McNamee & Co., of
Montreal, and the successful completion of the work was in a large
degree due to the energy displayed by the working member of that
firm--Mr. A.G. Nish, formerly engineer of the Montreal harbor.


THE CANAL

The canal was formed by "fencing in" a portion of the river-bed by an
embankment built about a hundred feet out from the north shore and
deepening the intervening space where necessary. There are two
locks--one placed a little above the foot of the rapid (see map), and
the other at the end of the dam. Wooden piers are built at the upper and
lower ends--the former being 800 ft. long, and the latter 300 ft; both
are about 29 ft. high and 35 ft. wide.

The embankment is built, as shown by the cross section, Fig. 6. On the
canal side of it there is a wall of rubble masonry F, laid in hydraulic
cement, connecting the two locks, and backed by a puddle wall, E, three
feet thick; next the river there is crib work, G, from ten to twenty
feet wide and the space between brick-work and puddle filled with earth.
The outer slope is protected with riprap, composed of large bowlders.
This had to be made very strong to prevent the destruction of the bank
by the immense masses of moving ice in spring.

The distance between the locks is 3,300 feet.

In building the embankment the crib-work was first put in and followed
by a part (in width) of the earth-bank. From that to the shore temporary
cross-dams were built at convenient distances apart and the space pumped
out by sections, when the necessary excavation was done, and the walls
and embankments completed. The earth was put down in layers of not more
than a foot deep at a time, so that the bank, when completed, was solid.
The water at site of it varied in depth from 15 feet at lower end to 2
feet at upper.

The locks are 200 ft. long in the clear between the gates, and 45 ft
wide in the chamber at the bottom. The walls of the lower one are 29 ft.
high, and of the upper one 31 ft They are from 10 to 12 ft thick at the
bottom,

The locks are built similar to those on the new Lachine and Welland
canals, of the very best cut stone masonry, laid in hydraulic cement.
The gates are 24 in. thick, made of solid timber, somewhat similar to
those in use on the St. Lawrence canals. They are suspended from anchors
at the hollow quoins, and work very easily. The miter sills are made of
26 in. square oak. The bottom of the lower lock iis timbered throughout,
but the upper one only at the recesses, the rock there being good.

[Illustration: MAP OF THE OTTAWA RIVER AT CARILLON RAPIDS.

SECTION OF RIVER AT DAM. NOTE.--THE LOWEST DOTTED LINE IS LOW WATER
BEFORETHE DAM WAS BUILT. THEN THE LINE OF HIGH WATER WAS ABOUT A FOOT
ABOVE WHAT IS CREST OF DAM NOW.]

The rise to be overcome by the two locks is 16 ft., but except in medium
water, is not equally distributed. In high water nearly the whole lift
is on the upper lock, and in low water the lower one. In the very lowest
known stage of the river there will never be less than 9 ft. on the
miter sills.

As mentioned at the beginning of this article, four locks were required
on the old military canal to accomplish what is now done by two.

The canal was opened in May, 1882, and has been a great success, the
only drawback--although slight--being that in high water the current for
about three-quarters of a mile above the upper pier, and at what was
formerly the Chute a Biondeau, is rather strong. These difficulties can
be easily overcome--the former by building an embankment from the pier
to Brophy's Island, the latter by removing some of the natural dam of
rock which once formed the "Chute."

The following are, in round numbers, the quantities of the principal
materials used:

Earth and puddle in embankment ...cub. yds. 148,500
Rock excavation, " 38,000
Riprap, " 6,600
Lock masonry " 14,200
Rubble masonry, " 16,600
Timber in cribs, lock bottoms and gates " 368,000
Wrought and cast iron, lb ................. 173,000
Stone filling cu yds ...................... 45,300
Concrete " 830

The total cost to date has been about $570,000, not including surveys,
engineering, etc.

The contractors for the canal, locks, etc., were Messrs. R. P. Cooke &
Co., of Brockville, Ont., who have built some large works in the States,
and who are now engaged building other extensive works for the Canadian
Government. The work here reflects great credit on their skill.

On the enlarged Grenville Canal, now approaching completion, there
are five locks, taking the place of the seven small ones built by the
Imperial Government. It will be open for navigation all through in the
spring of 1884, when steamers somewhat larger than the largest now
navigating the St. Lawrence between Montreal and Hamilton can pass up to
Ottawa City.--_Engineering News_.

* * * * *




DWELLING HOUSES--HINTS ON BUILDING--"HOME, SWEET HOME."

[Footnote: From a paper read before the Birmingham Architectural
Association, Jan 30, 1883]

By WILLIAM HENMAN, A.R.I.B.A.


My intention is to bring to your notice some of the many causes which
result in unhealthy dwellings, particularly those of the middle classes
of society. The same defects, it is true, are to be found in the palace
and the mansion, and also in the artisan's cottage; but in the former
cost is not so much a matter of consideration, and in the latter, the
requirements and appliances being less, the evils are minimized. It is
in the houses of the middle classes, I mean those of a rental at from
L50 to L150 per annum, that the evils of careless building and want
of sanitary precautions become most apparent. Until recently sanitary
science was but little studied, and many things were done a few years
since which even the self-interest of a speculative builder would not do
nowadays, nor would be permitted to do by the local sanitary authority.
Yet houses built in those times are still inhabited, and in many cases
sickness and even death are the result. But it is with shame I must
confess that, notwithstanding the advance which sanitary science has
made, and the excellent appliances to be obtained, many a house is now
built, not only by the speculative builder, but designed by professed
architects, and in spite of sanitary authorities and their by-laws,
which, in important particulars are far from perfect, are unhealthy, and
cannot be truly called sweet homes.

Architects and builders have much to contend with. The perverseness of
man and the powers of nature at times appear to combine for the express
purpose of frustrating their endeavors to attain sanitary perfection.
Successfully to combat these opposing forces, two things are above all
necessary, viz 1, a more perfect insight into the laws of nature, and a
judicious use of serviceable appliances on the part of the architect;
and, 2, greater knowledge, care, and trustworthiness on the part of
workmen employed. With the first there will be less of that blind
following of what has been done before by others, and by the latter the
architect who has carefully thought out the details of his sanitary work
will be enabled to have his ideas carried out in an intelligent manner.
Several cases have come under my notice, where, by reckless carelessness
or dense ignorance on the part of workmen, dwellings which might have
been sweet and comfortable if the architect's ideas and instructions had
been carried out, were in course of time proved to be in an unsanitary
condition. The defects, having been covered up out sight, were only made
known in some cases after illness or death had attacked members of the
household.

In order that we may have thoroughly sweet homes, we must consider the
localities in which they are to be situated, and the soil on which they
are to rest. It is an admitted fact that certain localities are more
generally healthy than others, yet circumstances often beyond their
control compel men to live in those less healthy. Something may, in
the course of time, be done to improve such districts by planting,
subdrainage, and the like. Then, as regards the soil; our earth has
been in existence many an age, generation after generation has come and
passed away, leaving behind accumulations of matter on its surface, both
animal and vegetable, and although natural causes are ever at the work
of purification, there is no doubt such accumulations are in many cases
highly injurious to health, not only in a general way, but particularly
if around, and worse still, under our dwellings. However healthy a
district is considered to be, it is never safe to leave the top soil
inclosed within the walls of our houses; and in many cases the subsoil
should be covered with a layer of cement concrete, and at times with
asphalt on the concrete. For if the subsoil be damp, moisture will rise;
if it be porous, offensive matter may percolate through. It is my belief
that much of the cold dampness felt in so many houses is caused by
moisture rising from the ground inclosed _within_ the outer walls.
Cellars are in many cases abominations. Up the cellar steps is a
favorite means of entrance for sickness and death. Light and air, which
are so essential for health and life, are shut out. If cellars are
necessary, they should be constructed with damp proof walls and floors;
light should be freely admitted; every part must be well ventilated,
and, above all, no drain of any description should be taken in. If they
be constructed so that water cannot find its way through either walls or
floors, where is the necessity of a drain? Surely the floors can be
kept clean by the use of so small an amount of water that it would be
ridiculous specially to provide a drain.

The next important but oft neglected precaution is to have a good damp
course over the _whole_ of the walls, internal as well as external. I
know that for the sake of saving a few pounds (most likely that they may
be frittered away in senseless, showy features) it often happens, that
if even a damp course is provided in the outer walls, it is dispensed
with in the interior walls. This can only be done with impunity on
really dry ground, but in too many cases damp finds its way up, and, to
say the least, disfigures the walls. Here I would pause to ask: What is
the primary reason for building houses? I would answer that, in this
country at least, it is in order to protect ourselves from wind and
weather. After going to great expense and trouble to exclude cold and
wet by means of walls and roofs, should we not take as much pains to
prevent them using from below and attacking us in a more insidious
manner? Various materials may be used as damp courses. Glazed
earthenware perforated slabs are perhaps the best, when expense is no
object. I generally employ a course of slates, breaking joint with a
good bed of cement above and below; it answers well, and is not very
expensive. If the ground is irregular, a layer of asphalt is more easily
applied. Gas tar and sand are sometimes used, but it deteriorates and
cannot be depended upon for any length of time. The damp course should
invariably be placed _above_ the level of the ground around the
building, and _below_ the ground floor joists. If a basement story is
necessary, the outer walls below the ground should be either built
hollow, or coated externally with some substance through which wet
cannot penetrate. Above the damp course, the walls of our houses must
be constructed of materials which will keep out wind and weather. Very
porous materials should be avoided, because, even if the wet does not
actually find its way through, so much is absorbed during rainy weather
that in the process of drying much cold is produced by evaporation. The
fact should be constantly remembered, viz., that evaporation causes
cold. It can easily be proved by dropping a little ether upon the bulb
of a thermometer, when it will be seen how quickly the mercury falls,
and the same effect takes place in a less degree by the evaporation of
water. Seeing, then, that evaporation from so small a surface can
lower temperature so many degrees, consider what must be the effect of
evaporation from the extensive surfaces of walls inclosing our houses.
This experiment (thermometer with bulb inclosed in linen) enables me as
well to illustrate that curious law of nature which necessitates the
introduction of a damp course in the walls of our buildings; it is known
as capillary or molecular attraction, and breaks through that more
powerful law of gravitation, which in a general way compels fluids to
find their own level. You will notice that the piece of linen over the
bulb of the thermometer, having been first moistened, continues moist,
although only its lower end is in water, the latter being drawn up by
capillary attraction; or we have here an illustration more to the point:
a brick which simply stands with its lower end in water, and you can
plainly see how the damp has risen.

From these illustrations you will see how necessary it is that the brick
and stone used for outer walls should be as far as possible impervious
to wet; but more than that, it is necessary the jointing should be
non-absorbent, and the less porous the stone or brick, the better able
must the jointing be to keep out wet, for this reason, that when rain is
beating against a wall, it either runs down or becomes absorbed. If both
brick and mortar, or stone and mortar be porous, it becomes absorbed; if
all are non-porous, it runs down until it finds a projection, and then
drops off; but if the brick or stone is non-porous, and the mortar
porous, the wet runs down the brick or stone until it arrives at the
joint, and is then sucked inward. It being almost impossible to obtain
materials quite waterproof, suitable for external walls, other means
must be employed for keeping our homes dry and comfortable. Well built
hollow walls are good. Stone walls, unless very thick, should be lined
with brick, a cavity being left between. A material called Hygeian Rock
Building Composition has lately been introduced, which will, I believe,
be found of great utility, and, if properly applied, should insure a dry
house. A cavity of one-half an inch is left between the outer and inner
portion of the wall, whether of brick or stone, which, as the building
rises, is run in with the material made liquid by heat; and not only is
the wall waterproofed thereby, but also greatly strengthened. It may
also be used as a damp course.

Good, dry walls are of little use without good roofs, and for a
comfortable house the roofs should not only be watertight and
weathertight, but also, if I may use the term, heat-tight. There can be
no doubt that many houses are cold and chilly, in consequence of the
rapid radiation of heat through the thin roofs, if not through thin and
badly constructed walls. Under both tiles and slates, but particularly
under the latter, there should be some non-conducting substance, such
as boarding, or felt, or pugging. Then, in cold weather heat will be
retained; in hot weather it will be excluded. Roofs should be of a
suitable pitch, so that neither rain nor snow can find its way in in
windy weather. Great care must be taken in laying gutters and flats.
With them it is important that the boarding should be well laid in
narrow widths, and in the direction of the fall; otherwise the boards
cockle and form ridges and furrows in which wet will rest, and in time
decay the metal.

After having secured a sound waterproof roof, proper provision must be
made for conveying therefrom the water which of necessity falls on it in
the form of rain. All eaves spouting should be of ample size, and the
rain water down pipes should be placed at frequent intervals and of
suitable diameter. The outlets from the eaves spouting should not be
contracted, although it is advisable to cover them with a wire grating
to prevent their becoming choked with dead leaves, otherwise the water
will overflow and probably find its way through the walls. All joints
to the eaves spouting, and particularly to the rain-water down pipes,
should be made watertight, or there is great danger, when they are
connected with the soil drains, that sewer gas will escape at the joints
and find its way into the house at windows and doors. There should be a
siphon trap at the bottom of each down pipe, unless it is employed as a
ventilator to the drains, and then the greatest care should be exercised
to insure perfect jointings, and that the outlet be well above all
windows. Eaves spouting and rain-water down pipes should be periodically
examined and cleaned out. They ought to be painted inside as well as
out, or else they will quickly decay, and if of iron they will rust,
flake off, and become stopped.

It is impossible to have a sweet home where there is continual dampness.
By its presence chemical action and decay are set up in many substances
which would remain in a quiescent state so long as they continued dry.
Wood will rot; so will wall papers, the paste used in hanging them,
and the size in distemper, however good they have been in the first
instance; then it is that injurious exhalations are thrown off, and the
evil is doubtless very greatly increased if the materials are bad in
themselves. Quickly grown and sappy timber, sour paste, stale size, and
wall papers containing injurious pigments are more easily attacked, and
far more likely to fill the house with bad smells and a subtile poison.
Plaster to ceilings and walls is quickly damaged by wet, and if improper
materials, such as road drift, be used in its composition, it may become
most unsavory and injurious to health. The materials for plaster cannot
be too carefully selected, for if organic matter be present, the result
is the formation of nitrates and the like, which combine with lime and
produce deliquescent salts, viz, those which attract moisture. Then,
however impervious to wet the walls, etc., may be, signs of dampness
will be noticed wherever there is a humid atmosphere, and similar evils
will result as if wet had penetrated from the exterior. Organic matter
coming into contact with plaster, and even the exhalations from human
beings and animals, will in time produce similar effects. Hence stables,
water closets, and rooms which are frequently crowded with people,
unless always properly ventilated, will show signs of dampness and
deterioration of the plaster work; wall paper will become detached from
the walls, paint will blister and peel off, and distemper will lose its
virtue. To avoid similar mishaps, sea sand, or sand containing salt,
should never be used either for plaster or mortar. In fact, it is
necessary that the materials for mortar should be as free from salts and
organic matter as those used for plaster, because the injurious effects
of their presence will be quickly communicated to the latter.

Unfortunately, it is not alone by taking precaution against the
possibility of having a damp house that we necessarily insure a "sweet
home." The watchful care of the architect is required from the cutting
of the first sod until the finishing touches are put on the house. He
must assure himself that all is done, and nothing left undone which is
likely to cause a nuisance, or worse still, jeopardize the health of
the occupiers. Yet, with all his care and the employment of the best
materials and apparatus at his command, complete success seems scarcely
possible of attainment. We have all much to learn, many things must
be accomplished and difficulties overcome, ere we can "rest and be
thankful."

It is impossible for the architect to attempt to solve all the problems
which surround this question. He must in many cases employ such
materials and such apparatus as can be obtained; nevertheless, it is his
duty carefully to test the value of such materials and apparatus as
may be obtainable, and by his experience and scientific knowledge to
determine which are best to be used under varying circumstances.

But to pass on to other matters which mar the sweetness of home. With
many, I hold that the method usually employed for warming our dwellings
is wasteful, dirty, and often injurious to health. The open fire,
although cheerful in appearance, is justly condemned. It is wasteful,
because so small a percentage of the value of the fuel employed is
utilized. It is dirty, because of the dust and soot which result
therefrom. It is unhealthy, because of the cold draughts which in its
simplest form are produced, and the stifling atmosphere which pervades
the house when the products of imperfect combustion insist, as they
often do, in not ascending the flues constructed for the express purpose
of carrying them off; and even when they take the desired course, they
blacken and poison the external atmosphere with their presence. Some of
the grates known as ventilating grates dispose of one of the evils of
the ordinary open fire, by reducing the amount of cold draught caused by
the rush of air up the flues. This is effected, as you probably know, by
admitting air direct from the outside of the house to the back of the
grate, where it is warmed, and then flows into the rooms to supply the
place of that which is drawn up the chimneys. Provided such grates act
properly and are well put together, so that there is no possibility of
smoke being drawn into the fresh air channels, and that the air to
be warmed is drawn from a pure source, they may be used with much
advantage; although by them we must not suppose perfection has been
attained. The utilization of a far greater percentage of heat and the
consumption of all smoke must be aimed at. It is a question if such can
be accomplished by means of an open fire, and it is a difficult matter
to devise a method suited in every respect to the warming of our
dwellings, which at the same time is equally cheering in appearance.
So long as we are obliged to employ coal in its crude form for heating
purposes, and are content with the waste and dirt of the open fire, we
must be thankful for the cheer it gives in many a home where there are
well constructed grates and flues, and make the best use we can of the
undoubted ventilating power it possesses.

A constant change of air in every part of our dwellings is absolutely
necessary that we may have a "sweet home," and the open fireplace with
its flue materially helps to that end; but unless in every other respect
the house is in a good sanitary condition, the open fire only adds to
the danger of residing in such a house, because it draws the impure air
from other parts into our living rooms, where it is respired. Closed
stoves are useful in some places, such as entrance halls. They are more
economical than the open fireplaces; but with them there is danger of
the atmosphere, or rather, the minute particles of organic matter always
floating in the air, becoming burnt and so charging the atmosphere with
carbonic acid. The recently introduced slow-combustion stoves obviate
this evil.

It is possible to warm our houses without having separate fireplaces in
each room, viz., by heated air, hot water, or steam; but there are
many difficulties and some dangers in connection therewith which I
can scarcely hope to see entirely overcome. In America steam has been
employed with some success, and there is this advantage in its use, that
it can be conveyed a considerable distance. It is therefore possible
to have the furnace and boilers for its production quite away from the
dwelling houses and to heat several dwellings from one source, while at
the same time it can be employed for cooking purposes. In steam, then,
we have a useful agent, which might with advantage be more generally
employed; but when either it or hot water be used for heating purposes,
special and adequate means of ventilation must be employed. Gas stoves
are made in many forms, and in a few cases can be employed with
advantage; but I believe they are more expensive than a coal fire, and
it is most difficult to prevent the products of combustion finding their
way into the dwellings. Gas is a useful agent in the kitchen for cooking
purposes, but I never remember entering a house where it was so employed
without at once detecting the unpleasant smell resulting. It is rare to
find any special means for carrying off the injurious fumes, and without
such I am sure gas cooking stoves cannot be healthy adjuncts to our
homes.

The next difficulty we have to deal with is artificial lighting.
Whether we employ candle, oil lamp, or gas, we may be certain that the
atmosphere of our rooms will become contaminated by the products of
combustion, and health must suffer. In order that such may be obviated,
it must be an earnest hope that ere long such improvements will be made
in electric lighting, that it may become generally used in our homes as
well as in all public buildings. Gas has certainly proved itself a very
useful and comparatively inexpensive illuminating power, but in many
ways it contaminates the atmosphere, is injurious to health, and
destructive to the furniture and fittings of our homes. Leakages from
the mains impregnate the soil with poisonous matter, and it rarely
happens that throughout a house there are no leakages. However small
they may be, the air becomes tainted. It is almost impossible, at times,
to detect the fault, or if detected, to make good without great injury
to other work, in consequence of the difficulty there is in getting at
the pipes, as they are generally embedded in plaster, etc. All gas pipes
should be laid in positions where they can be easily examined, and, if
necessary, repaired without much trouble. In France it is compulsory
that all gas pipes be left exposed to view, except where they must of
necessity pass through the thickness of a wall or floor, and it would be
a great benefit if such were required in this country.

The cooking processes which necessarily go on often result in unpleasant
odors pervading our homes. I cannot say they are immediately prejudicial
to health; but if they are of daily or frequent occurrence, it is more
than probable the volatile matters which are the cause of the odors
become condensed upon walls, ceiling, or furniture, and in time undergo
putrefaction, and so not only mar the sweetness of home, but in addition
affect the health of the inmates. Cooking ranges should therefore be
constructed so as to carry off the fumes of cooking, and kitchens must
be well ventilated and so placed that the fumes cannot find their way
into other parts of the dwelling. In some houses washing day is an
abomination. Steam and stife then permeate the building, and, to say the
least, banish sweetness and comfort from the home. It is a wonder that
people will, year after year, put up with such a nuisance.

If washing must be done home, the architect may do something to lessen
the evil by placing the washhouse in a suitable position disconnected
from the living part of the house, or by properly ventilating it and
providing a well constructed boiler and furnace, and a flue for carrying
off the steam.

There is daily a considerable amount of refuse found in every home, from
the kitchen, from the fire-grate, from the sweeping of rooms, etc., and
as a rule this is day after day deposited in the ash-pit, which but
too often is placed close to the house, and left uncovered. If it were
simply a receptacle for the ashes from the fire-grates, no harm would
result, but as all kinds of organic matter are cast in and often allowed
to remain for weeks to rot and putrefy, it becomes a regular pest box,
and to it often may be traced sickness and death. It would be a wise
sanitary measure if every constructed ash pit were abolished. In place
thereof I would substitute a galvanized iron covered receptacle of but
moderate size, mounted upon wheels, and it should be incumbent on the
local authorities to empty same every two or three days. Where there are
gardens all refuse is useful as manure, and a suitable place should be
provided for it at the greatest distance from the dwellings. Until the
very advisable reform I have just mentioned takes place, it would be
well if refuse were burnt as soon as possible. With care this may be
done in a close range, or even open fire without any unpleasant smells,
and certainly without injury to health. It must be much more wholesome
to dispose of organic matter in that way while fresh than to have it
rotting and festering under our very noses.

A greater evil yet is the privy. In the country, where there is no
complete system of drainage, it may be tolerated when placed at a
distance from the house; but in a crowded neighborhood it is an
abomination, and, unless frequently emptied and kept scrupulously clean,
cannot fail to be injurious to health. Where there is no system of
drainage, cesspools must at times be used, but they should be avoided as
much as possible. They should never be constructed near to dwellings,
and must always be well ventilated. Care should be taken to make them
watertight, otherwise the foul matter may percolate through the ground,
and is likely to contaminate the water supply. In some old houses
cesspools have been found actually under the living rooms.

I would here also condemn the placing of r. w. tanks under any portion
of the dwelling house, for many cases of sickness and death have been
traced to the fact of sewage having found its way through, either by
backing up the drains, or by the ignorant laying of new into old
drains. Earth closets, if carefully attended to, often emptied, and the
receptacles cleaned out, can be safely employed even within doors;
but in towns it is difficult to dispose of the refuse, and there must
necessarily be a system of drainage for the purpose of taking off the
surface water; it is thereupon found more economical to carry away all
drainage together, and the water closet being but little trouble, and,
if properly looked after, more cleanly in appearance, it is generally
preferred, notwithstanding the great risks which are daily run in
consequence of the chance of sewer-gas finding an entrance into the
house by its means. After all, it is scarcely fair to condemn outright
the water closet as the cause of so many of the ills to which flesh is
subject. It is true that many w. c. apparatus are obviously defective
in construction, and any architect or builder using such is to be
condemned. The old pan closet, for instance, should be banished. It is
known to be defective, and yet I see it is still made, sold, and fixed,
in dwelling houses, notwithstanding the fact that other closet pans far
more simple and effective can be obtained at less cost. The pan of the
closet should be large, and ought to retain a layer of water at the
bottom, which, with the refuse, should be swept out of the pan by the
rush of water from the service pipe. The outlet may be at the side
connected with a simple earthenware s-trap with a ventilating outlet at
the top, from which a pipe may be taken just through the wall. From the
S-trap I prefer to take the soil pipe immediately through the wall, and
connect with a strong 4 in. iron pipe, carefully jointed, watertight,
and continued of the same size to above the tops of all windows. This
pipe at its foot should be connected with a ventilating trap, so that
all air connection is cut off between the house and the drains. All
funnel-shaped w. c. pans are objectionable, because they are so liable
to catch and retain the dirt.

Wastes from baths, sinks, and urinals should also be ventilated and
disconnected from the drains as above, or else allowed to discharge
above a gulley trap. Excrement, etc., must be quickly removed from the
premises if we are to have "sweet homes," and the w.c. is perhaps the
most convenient apparatus, when properly constructed, which can be
employed. By taking due precaution no harm need be feared, or will
result from its use, provided that the drains and sewers are rightly
constructed and properly laid. It is then to the sewers, drains, and
their connections our attention must be specially directed, for in the
majority of cases they are the arch-offenders. The laying of main sewers
has in most cases been intrusted to the civil engineer, yet it often
happens architects are blamed, and unjustly so, for the defective
work over which they had no control. When the main sewers are badly
constructed, and, as a result, sewer gas is generated and allowed to
accumulate, ordinary precautions may be useless in preventing its
entrance by some means or other to our homes, and special means and
extra precautions must be adopted. But with well constructed and
properly ventilated sewers, every architect and builder should be able
to devise a suitable system of house drainage, which need cause no
fear of danger to health. The glazed stoneware pipe, now made of any
convenient size and shape, is an excellent article with which to
construct house-drains. The pipes should be selected, well burnt, well
glazed, and free from twist. Too much care cannot be exercised in
properly laying them. The trenches should be got out to proper falls,
and unless the ground is hard and firm, the pipes should be laid upon a
layer of concrete to prevent the chance of sinking. The jointing must be
carefully made, and should be of cement or of well tempered clay, care
being taken to wipe away all projecting portions from the inside of the
pipes. A clear passage-way is of the utmost importance. Foul drains are
the result of badly joined and irregularly laid pipes, wherein matter
accumulates, which in time ferments and produces sewer-gas. The common
system of laying drains with curved angles is not so good as laying them
in straight lines from point to point, and at every angle inserting
a man-hole or lamp-hole, This plan is now insisted upon by the Local
Government Board for all public buildings erected under their authority.
It might, with advantage, be adopted for all house-drains.

Now, in consequence of the trouble and expense attending the opening up
and examination of a drain, it may often happen that although defects
are suspected or even known to exist, they are not remedied until
illness or death is the result of neglect. But with drains laid in
straight lines, from point to point, with man holes or lamp holes at the
intersections, there is no reason why the whole system may not easily be
examined at any time and stoppages quickly removed. The man holes and
lamp-holes may, with advantage, be used as means for ventilating the
drains and also for flushing them. It is of importance that each house
drain should have a disconnecting trap just before it enters the main
sewer. It is bad enough to be poisoned by neglecting the drainage to
one's own property, but what if the poison be developed elsewhere, and
by neglect permitted to find its way to us. Such will surely happen
unless some effective means be employed for cutting off all air
connection between the house-drains and the main sewer. I am firmly
convinced that simply a smoky chimney, or the discovery of a fault in
drainage weighs far more, in the estimation of a client in forming his
opinion of the ability of an architect, than the successful carrying out
of an artistic design. By no means do I disparage a striving to attain
artistic effectiveness, but to the study of the artistic, in domestic
architecture at least, add a knowledge of sanitary science, and foster a
habit of careful observation of causes and effects. Comfort is demanded
in the home, and that cannot be secured unless dwellings are built and
maintained with perfect sanitary arrangements and appliances.--_The
Building News_.

* * * * *




HOUSE AT HEATON


This house, which belongs to Mr J. N. D'Andrea, is built on the Basque
principle, under one roof, with covered balconies on the south side, the
northside being kept low to give the sun an opportunity of shining in
winter on the house and greenhouse adjacent, as well as to assist in the
more picturesque grouping of the two. On this side is placed, approached
by porch and lobby, the hall with a fireplace of the "olden time,"
lavatory, etc., butler's pantry, w. c., staircase, larder, kitchen,
scullery, stores, etc.

On the south side are two sitting rooms, opening into a conservatory.
There are six bedrooms, a dining-room, bath room, and housemaid's sink.

The walls are built of colored wall stones known as "insides," and
half-timbered brickwork covered with the Portland cement stucco,
finished Panan, and painted a cream-color.

All the interior woodwork is of selected pitch pine, the hall being
boarded throughout. Colored lead light glass is introduced in the upper
parts of the windows in every room, etc.

The architect is Mr. W. A. Herbert Martin, of Bradford.--_Architect_

[Illustration: HOUSE AT HEATON, BRADFORD.]

* * * * *




A MANSARD ROOF DWELLING.


The principal floor of this design is elevated three feet above the
surface of the ground, and is approached by the front steps leading to
the platform. The height of the first floor is eleven feet, the second
ten feet, and the cellar six feet six inches in the clear. The porch is
so constructed that it can be put on either the front or side of the
house, as it may suit the owner. The rooms, eight in number, are airy
and of convenient size. The kitchen has a range, sink, and boiler, and
a large closet, to be used as a pantry. The windows leading out to the
porch will run to the floor, with heads running into the walls. In the
attic the chambers are 10x10 feet, 13x14 feet, 12x13 feet, 10x101/2 feet,
and a hall 6 feet wide, with large closets and cupboards for each
chamber. The building is so constructed that an addition can be made
to the rear any time by using the present kitchen as a dining room and
building a new kitchen.

[Illustration: A MANSARD ROOF DWELLING. First Floor.]

[Illustration: A MANSARD ROOF DWELLING. Second Floor.]

These plans will prove suggestive to those contemplating the building
of a new house, even if radical changes are made in the accompanying
designs.--_American Cultivator_.

[Illustration: A MANSARD ROOF DWELLING. Front Elevation.]

* * * * *




THE HISTORY OF THE ELECTRIC TELEGRAPH.

[Footnote: Aug. Guerout in _La Lurmiere Electrique_.]


An endeavor has often been made to carry the origin of the electric
telegraph back to a very remote epoch by a reliance on those more or
less fanciful descriptions of modes of communication based upon the
properties of the magnet.

It will prove not without interest before entering into the real history
of the telegraph to pass in review the various documents that relate to
the subject.

In continuation of the 21st chapter of his _Magia naturalis_, published
in 1553, J. B. Porta cites an experiment that had been made with the
magnet as a means of telegraphing. In 1616, Famiano Strada, in his
_Prolusiones Academicae_, takes up this idea, and speaks of the
possibility of two persons communicating by the aid of two magnetized
needles influenced by each other at a distance. Galileo, in _Dialogo
intorno_, written between 1621 and 1632 and Nicolas Caboeus, of Ferrara,
in his _Philosophia magnetica_, both reproduce analogous descriptions,
not however without raising doubts as to the possibility of such a
system.

A document of the same kind, to which great importance has been attached
is found in the _Recreations mathematiques_ published at Rouen in 1628,
under the pseudonym of Van Elten, and reprinted several times since,
with the annotations and additions of Mydorge and Hamion and which must,
it appears, be attributed to the Jesuit Leurechon. In his chapter on the
magnet and the needles that are rubbed therewith, we find the following
passage.

"Some have pretended that, by means of a magnet or other like stone,
absent persons might speak with one another. For example, Claude being
at Paris, and John at Rome, if each had a needle that had been rubbed
with some stone, and whose virtue was such that in measure as one needle
moved at Paris the other would move just the same at Rome, and if Claude
and John each had an alphabet, and had agreed that they would converse
with each other every afternoon at 6 o'clock, and the needle having made
three and a half revolutions as a signal that Claude, and no other,
wished to speak to John, then Claude wishing to say to him that the king
is at Paris would cause his needle to move, and stop at T, then at H,
then at E, then at K, I, N, G and so on. Now, at the same time, John's
needle, according with Claude's, would begin to move and then stop at
the same letters, and consequently it would be easily able to write or
understand what the other desired to signify to it. The invention is
beautiful, but I do not think there can be found in the world a magnet
that has such a virtue. Neither is the thing expedient, for treason
would be too frequent and too covert."

The same idea was also indicated by Joseph Glanville in his _Scepsis
scientifica_, which appeared in 1665, by Father Le Brun, in his
_Histoire critique des pratiques superstitieuses_, and finally by the
Abbe Barthelemy in 1788.

The suggestion offered by Father Kircher, in his _Magnes sive de arte
magnetica_, is a little different from the preceding. The celebrated
Jesuit father seeks however, to do nothing more than to effect a
communication of thoughts between two rooms in the same building. He
places, at short distances from each other, two spherical vessels
carrying on their circumference the letters of the alphabet, and each
having suspended within it, from a vertical wire a magnetized figure. If
one of these latter he moved, all the others must follow its motions,
one after the other, and transmission will thus be effected from the
first vessel to the last. Father Kircher observes that it is necessary
that all the magnets shall be of the same strength, and that there shall
be a large number of them, which is something not within the reach
of everybody. This is why he points out another mode of transmitting
thought, and one which consists in supporting the figures upon vertical
revolving cylinders set in motion by one and the same cord hidden with
in the walls.

There is no need of very thoroughly examining all such systems of
magnetic telegraphy to understand that it was never possible for them to
have a practical reality, and that they were pure speculations which it
is erroneous to consider as the first ideas of the electric telegraph.

We shall make a like reserve with regard to certain apparatus that
have really existed, but that have been wrongly viewed as electric
telegraphs. Such are those of Comus and of Alexandre. The first of these
is indicated in a letter from Diderot to Mlle. Voland, dated July 12,
1762. It consisted of two dials whose hands followed each other at a
distance, without the apparent aid of any external agent. The fact
that Comus published some interesting researches on electricity in the
_Journal de Physique_ has been taken as a basis for the assertion that
his apparatus was a sort of electrical discharge telegraph in which the
communication between the two dials was made by insulated wires hidden
in the walls. But, if it be reflected how difficult it would have been
at that epoch to realize an apparatus of this kind, if it be remembered
that Comus, despite his researches on electricity, was in reality only a
professor of physics to amuse, and if the fact be recalled that cabinets
of physics in those days were filled with ingenious apparatus in which
the surprising effects were produced by skillfully concealed magnets, we
shall rather be led to class among such apparatus the so-called "Comus
electric telegraph."

We find, moreover, in Guyot's _Recreations physiques et
mathematiques_--a work whose first edition dates back to the time at
which Comus was exhibiting his apparatus--a description of certain
communicating dials that seem to be no other than those of the
celebrated physicist, and which at all events enables us to understand
how they worked.

Let one imagine to himself two contiguous chambers behind which ran
one and the same corridor. In each chamber, against the partition that
separated it from the corridor, there was a small bracket, and upon the
latter, and very near the wall, there was a wooden dial supported on a
standard, but in no wise permanently fixed upon the bracket. Each dial
carried a needle, and each circumference was inscribed with twenty-five
letters of the alphabet. The experiment that was performed with these
dials consisted in placing the needle upon a letter in one of the
chambers, when the needle of the other dial stopped at the same letter,
thus making it possible to transmit words and even sentences. As for the
means of communication between the two apparatus, that was very simple:
One of the two dials always served as a transmitter, and the other as a
receiver. The needle of the transmitter carried along in its motion
a pretty powerful magnet, which was concealed in the dial, and which
reacted through the partition upon a very light magnetized needle that
followed its motions, and indicated upon an auxiliary dial, to a person
hidden in the corridor, the letter on which the first needle had been
placed. This person at once stepped over to the partition corresponding
to the receiver, where another auxiliary dial permitted him to properly
direct at a distance the very movable needle of the receiver. Everything
depended, as will be seen, upon the use of the magnet, and upon a deceit
that perfectly accorded with Comus' profession. There is, then, little
thought in our opinion that if the latter's apparatus was not exactly
the one Guyot describes, it was based upon some analogous artifice.

Jean Alexandre's telegraph appears to have borne much analogy with
Comus'. Its inventor operated it in 1802 before the prefect of
Indre-et-Loire. As a consequence of a report addressed by the prefect of
Vienne to Chaptal, and in which, moreover, the apparatus in question was
compared to Comus', Alexandre was ordered to Paris. There he refused to
explain upon what principle his invention was based, and declared that
he would confide his secret only to the First Consul. But Bonaparte,
little disposed to occupy himself with such an affair, charged Delambre
to examine it and address a report to him. The illustrious astronomer,
despite the persistence with which Alexandre refused to give up his
secret to him, drew a report, the few following extracts from which
will, we think, suffice to edify the reader:

"The pieces that the First Consul charged me to examine did not contain
enough of detail to justify an opinion. Citizen Beauvais (friend and
associate of Alexandre) knows the inventor's secret, but has promised
him to communicate it to no one except the First Consul. This
circumstance might enable me to dispense with any report; for how judge
of a machine that one has not seen and does not know the agent of? All
that is known is that the _telegraphe intime_ consists of two like
boxes, each carrying a dial on whose circumference are marked the
letters of the alphabet. By means of a winch, the needle of one dial is
carried to all the letters that one has need to use, and at the same
instant the needle of the second box repeats, in the same order, all the
motions and indications of the first.

"When these two boxes are placed in two separate apartments, two persons
can write to and answer one another, without seeing or being seen by one
another, and without any one suspecting their correspondence. Neither
night nor fog can prevent the transmission of a dispatch.... The
inventor has made two experiments--one at Portiers and the other at
Tours--in the presence of the prefects and mayors, and the record shows
that they were fully successful. To-day, the inventor and his associate
ask that the First Consul be pleased to permit one of the boxes to be
placed in his apartment and the other at the house of Consul Cambaceres
in order to give the experiment all the _eclat_ and authenticity
possible; or that the First Consul accord a ten minutes' interview to
citizen Beauvais, who will communicate to him the secret, which is
so easy that the simple _expose_ of it would be equivalent to a
demonstration, and would take the place of an experiment.... If, as one
might be tempted to believe from a comparison with a bell arrangement,
the means adopted by the inventor consisted in wheels, movements,
and transmitting pieces, the invention would be none the less
astonishing.... If, on the contrary, as the Portier's account seems to
prove, the means of communication is a fluid, there would be the more
merit in his having mastered it to such a point as to produce so regular
and so infallible effects at such distances.... But citizen Beauvais
... desires principally to have the First Consul as a witness and
appreciator.... It is to be desired, then, that the First Consul shall
consent to hear him, and that he may find in the communication that will
be made to him reasons for giving the invention a good reception and for
properly rewarding the inventor."

But Bonaparte remained deaf, and Alexandre persisted in his silence, and
died at Angers, in 1832, in great poverty, without having revealed his
secret.

As, in 1802, Volta's pile was already invented, several authors have
supposed an application of it in Alexandre's apparatus. "Is it not
allowable to believe," exclaims one of these, "that the electric
telegraph was at that time discovered?" We do not hesitate to respond in
the negative. The pile had been invented for too short a time, and too
little was then known of the properties of the current, to allow a
man so destitute of scientific knowledge to so quickly invent all the
electrical parts necessary for the synchronic operation of the two
needles. In this _telegraphe intime_ we can only see an apparatus
analogous to the one described by Guyot, or rather a synchronism
obtained by means of cords, as in Kircher's arrangement. The fact that
Alexandre's two dials were placed on two different stories, and distant,
horizontally, fifteen meters, in nowise excludes this latter mode of
transmission. On another hand, the mystery in which Alexandre was
shrouded, his declaration relative to the use of a fluid, and the
assurance with which he promised to reveal his secret to the First
Consul, prove absolutely nothing, for too often have the most profoundly
ignorant people--the electric girl, for example--befooled learned bodies
by the aid of the grossest frauds. From the standpoint of the history
of the electric telegraph, there is no value, then, to be attributed to
this apparatus of Alexandre, any more than there is to that of Comus or
to _any_ of the dreams based upon the properties of the magnet.

The history of the electric telegraph really begins with 1753, the date
at which is found the first indication of a telegraph truly based upon
the use of electricity. This telegraph is described in a letter written
by Renfrew, dated Feb. 1, 1753, and signed with the initials "C.M.,"
which, in all probability, were those of a savant of the time--Charles
Marshall. A few extracts from this letter will give an idea of the
precision with which the author described his invention:

"Let us suppose a bundle of wires, in number equal to that of the
letters of the alphabet, stretched horizontally between two given
places, parallel with each other and distant from each other one inch.

"Let us admit that after every twenty yards the wires are connected to a
solid body by a juncture of glass or jeweler's cement, so as to prevent
their coming in contact with the earth or any conducting body, and so
as to help them to carry their own weight. The electric battery will be
placed at right angles to one of the extremities of the wires, and the
bundle of wires at each extremity will be carried by a solid piece of
glass. The portions of the wires that run from the glass support to the
machine have sufficient elasticity and stiffness to return to their
primitive position after having been brought into contact with the
battery. Very near to this same glass support, on the opposite side,
there descends a ball suspended from each wire, and at a sixth or a
tenth of an inch beneath each ball there is placed one of the letters of
the alphabet written upon small pieces of paper or other substance light
enough to be attracted and raised by the electrified ball. Besides this,
all necessary arrangements are taken so that each of these little papers
shall resume its place when the ball ceases to attract.

[Illustration: FIG. 1.--LESAGE'S TELEGRAPH.]

"All being arranged as above, and the minute at which the correspondence
is to begin having been fixed upon beforehand, I begin the conversation
with my friend at a distance in this way: I set the electric machine
in motion, and, if the word that I wish to transcribe is 'Sir,' for
example, I take, with a glass rod, or with any other body electric
through itself or insulating, the different ends of the wires
corresponding to the three letters that compose the word. Then I press
them in such a way as to put them in contact with the battery. At the
same instant, my correspondent sees these different letters carried in
the same order toward the electrified balls at the other extremity of
the wires. I continue to thus spell the words as long as I judge proper,
and my correspondent, that he may not forget them, writes down the
letters in measure as they rise. He then unites them and reads the
dispatch as often as he pleases. At a given signal, or when I desire it,
I stop the machine, and, taking a pen, write down what my friend sends
me from the other end of the line."

The author of this letter points out, besides, the possibility of
keeping, in the first place, all the springs in contact with the
battery, and, consequently, all the letters attracted, and of indicating
each letter by removing its wire from the battery, and consequently
making it fall. He even proposed to substitute bells of different sounds
for the balls, and to produce electric sparks upon them. The sound
produced by the spark would vary according to the bell, and the letters
might thus be heard.

Nothing, however, in this document authorizes the belief that Charles
Marshall ever realized his idea, so we must proceed to 1774 to find
Lesage, of Geneva, constructing a telegraph that was based upon the
principle indicated twenty years before in the letter of Renfrew.

The apparatus that Lesage devised (Fig. 1) was composed of 24 wires
insulated from one another by a non conducting material. Each of these
wires corresponded to a small pith ball suspended by a thread. On
putting an electric machine in communication with such or such a one of
these wires, the ball of the corresponding electrometer was repelled,
and the motion signaled the letter that it was desired to transmit. Not
content with having realized an electric telegraph upon a small scale,
Lesage thought of applying it to longer distances.

"Let us conceive," said he in a letter written June 22, 1782, to Mr.
Prevost, of Geneva, "a subterranean pipe of enameled clay, whose cavity
at about every six feet is separated by partitions of the same material,
or of glass, containing twenty-four apertures in order to give passage
to as many brass wires as these diaphragms are to sustain and keep
separated. At each extremity of this pipe are twenty-four wires that
deviate from one another horizontally, and that are arranged like the
keys of a clavichord; and, above this row of wire ends, are distinctly
traced the twenty-four letters of the alphabet, while beneath there is a
table covered with twenty-four small pieces of gold-leaf or other easily
attractable and quite visible bodies."

Lesage had thought of offering his secret to Frederick the Great; but
he did not do so, however, and his telegraph remained in the state of a
curious cabinet experiment. He had, nevertheless, opened the way, and,
dating from that epoch, we meet with a certain number of attempts at
electrostatic telegraphy. [1]

[Footnote 1: Advantage has been taken of a letter from Alexander Volta
to Prof. Barletti (dated 1777), indicating the possibility of firing his
electric pistol from a great distance, to attribute to him a part in the
invention of the telegraph. We have not shared in this opinion, which
appears to us erroneous, since Volta, while indicating the possibility
above stated, does not speak of applying such a fact to telegraphy.]

The first in date is that of Lemond, which is spoken of by Arthur Young
(October 16, 1787), in his _Voyage Agronomique en France_:

"In the evening," says he, "we are going to Mr. Lemond's, a very
ingenious mechanician, and one who has a genius for invention.... He has
made a remarkable discovery in electricity. You write two or three words
upon paper; he takes them with him into a room and revolves a machine
within a sheath at the top of which there is an electrometer--a pretty
little ball of feather pith. A brass wire is joined to a similar
cylinder, and electrified in a distant apartment, and his wife on
remarking the motions of the ball that corresponds, writes down the
words that they indicate; from whence it appears that he has formed an
alphabet of motions. As the length of the wire makes no difference in
the effect, a correspondence might be kept up from very far off, for
example with a besieged city, or for objects much more worthy of
attention. Whatever be the use that shall be made of it, the discovery
is an admirable one."

And, in fact, Lemond's telegraph was of the most interesting character,
for it was a single wire one, and we already find here an alphabet based
upon the combination of a few elementary signals.

The apparatus that next succeeds is the electric telegraph that Reveroni
Saint Cyr proposed in 1790, to announce lottery numbers, but as to the
construction of which we have no details. In 1794 Reusser, a German,
made a proposition a little different from the preceding systems, and
which is contained in the _Magazin fuer das Neueste aus der Physik und
Naturgeschichte_, published by Henri Voigt.

"I am at home," says Reusser, "before my electric machine, and I am
dictating to some one on the other side of the street a complete
letter that he is writing himself. On an ordinary table there is fixed
vertically a square board in which is inserted a pane of glass. To this
glass are glued strips of tinfoil cut out in such a way that the spark
shall be visible. Each strip is designated by a letter of the alphabet,
and from each of them starts a long wire. These wires are inclosed in
glass tubes which pass underground and run to the place whither the
dispatch is to be transmitted. The extremities of the wires reach a
similar plate of glass, which is likewise affixed to a table and
carries strips of tinfoil similar to the others. These strips are also
designated, by the same letters, and are connected by a return wire with
the table of him who wishes to dictate the message. If, now, he who is
dictating puts the external armature of a Leyden jar in contact with the
return wire, and the ball of this jar in contact with a metallic rod
touching that of the tinfoil strip which corresponds with the letter
which he wishes to dictate to the other, sparks will be produced upon
the nearest as well as upon the remotest strips, and the distant
correspondent, seeing such sparks, may immediately write down the letter
marked. Will an extended application of this system ever be made? That
is not the question; it is possible. It will be very expensive; but the
post hordes from Saint Petersburg to Lisbon are also very expensive,
and if any one should apply the idea on a large scale, I shall claim a
recompense."

Every letter, then, was signaled by one or several sparks that started
forth on the breaking of the strip; but we see nothing in this document
to authorize the opinion which has existed, that every tinfoil strip was
a sort of magic tablet upon which the sparks traced the very form of the
letter to be transmitted.

Voigt, the editor of the _Magazin_, adds, in continuation of Reusser's
communication: "Mr. Reusser should have proposed the addition to this
arrangement of a vessel filled with detonating gas which could be
exploded in the first place, by means of the electric spark, in order
to notify the one to whom something was to be dictated that he should
direct his attention to the strips of tinfoil."

This passage gives the first indication of the use of a special call for
the telegraph. The same year (1794), in a work entitled _Versuch ueber
Telegraphie und Telegraphen_, Boeckmann likewise proposed the use of the
pistol as a call signal, in conjunction with the use of a line composed
of two wires only, and of discharges in the air or a vacuum, grouped in
such a way as to form an alphabet.

Experiments like those indicated by Boeckmann, however, seem to have
been made previous to 1794, or at that epoch, at least, by Cavallo,
since the latter describes them in a _Treatise on Electricity_ written
in English, and a French translation of which was published in 1795.
In these experiments the length of the wires reached 250 English feet.
Cavallo likewise proposed to use as signals combustible or detonating
materials, and to employ as a call the noise made by the discharge of a
Leyden jar.

In 1796 occurred the experiments of Dr. Francisco Salva and of the
Infante D. Antonio. The following is what we may read on this subject in
the _Journal des Sciences_:

"Prince de la Paix, having learned that Dr. Francisco Salva had read
before the Royal Academy of Sciences of Barcelona a memoir on the
application of electricity to telegraphy, and that he had presented at
the same time an electric telegraph of his own invention, desired
to examine this machine in person. Satisfied as to the accuracy and
celerity with which we can converse with another by means of it, he
obtained for the inventor the honor of appearing before the king. Prince
de la Paix, in the presence of their majesties and of several lords,
caused the telegraph to converse to the satisfaction of the whole court.
The telegraph conversed some days afterward at the residence of the
Infante D. Antonio.

"His Highness expressed a desire to have a much completer one that
should have sufficient electrical power to communicate at great
distances on land and sea. The Infante therefore ordered the
construction of an electric machine whose plate should be more than
forty inches in diameter. With the aid of this machine His Highness
intends to undertake a series of useful and curious experiments that he
has proposed to Dr. D. Salva."

In 1797 or '98 (some authors say 1787), the Frenchman, Betancourt, put
up a line between Aranjuez and Madrid, and telegraphed through the
medium of discharges from a Leyden jar.

But the most interesting of the telegraphs based upon the use of static
electricity is without doubt that of Francis Ronalds, described by the
latter, in 1823, in a pamphlet entitled _Descriptions of an Electrical
Telegraph and of some other Electrical Apparatus_, but the construction
of which dates back to 1816.

What is peculiarly interesting in Ronalds' apparatus is that it presents
for the first time the use of two synchronous movements at the two
stations in correspondence.

The apparatus is represented in Fig. 2. It is based upon the
simultaneous working of two pith-ball electrometers, combined with the
synchronous running of two clock-work movements. At the two stations
there were identical clocks for whose second hand there had been
substituted a cardboard disk (Fig. 3), divided into twenty sectors. Each
of these latter contained one figure, one letter, and a conventional
word. Before each movable disk there was a screen, A (Fig. 2),
containing an aperture through which only one sector could, be seen at
a time. Finally, before each screen there was a pith-ball electrometer.
The two electrometers were connected together by means of a conductor
(C) passing under the earth, and which at either of its extremities
could be put in communication with either an electric machine or the
ground. A lever handle, J, interposed into the circuit a Volta's pistol,
F, that served as a call.

When one of the operators desired to send a dispatch to the other he
connected the conductor with the machine, and, setting the latter in
operation, discharged his correspondent's pistol as a signal. The call
effected, the first operator continued to revolve the machine so that
the balls of pith should diverge in the two electrometers. At the same
time the two clocks were set running. When the sender saw the word
"attention" pass before the slit in the screen he quickly discharged the
line, the balls of the two electrometers approached each other, and, if
the two clocks agreed perfectly, the correspondent necessarily saw in
the aperture in his screen the same word, "attention." If not, he moved
the screen in consequence, and the operation was performed over until
he could send, in his turn, the word "ready." Afterward, the sender
transmitted in the same way one of the three words, "letters,"
"figures," "dictionary," in order to indicate whether he wished to
transmit letters or figures, or whether the letters received, instead of
being taken in their true sense, were to be referred to a conventional
vocabulary got up in advance. It was after such preliminaries that the
actual transmission of the dispatch was begun. The pith balls, which
were kept constantly apart, approached each other at the moment the
letter to be transmitted passed before the aperture in the screen.

Ronalds, in his researches, busied himself most with the construction of
lines. He put up on the grounds near his dwelling an air line 8 miles
long; and, to do so, stretched fine iron wire in zigzag fashion between
two frames 18 meters apart. Each of these frames carried thirty-seven
hooks, to which the wire was attached through the intermedium of silk
cords. He laid, besides, a subterranean line of 525 feet at a depth of 4
feet. The wire was inclosed within thick glass tubes which were placed
in a trough of dry wood, of 2 inch section, coated internally and
externally with pitch. This trough was, moreover, filled full of pitch
and closed with a cover of wood. Ronalds preferred these subterranean
conductors to air lines. A portion of one of them that was laid by him
at Hammersmith figured at the Exhibition of 1881, and is shown in Fig.
4.

Nearly at the epoch at which Ronalds was experimenting in England,
a certain Harrisson Gray Dyar was also occupying himself with
electrostatic telegraphy in America. According to letters published only
in 1872 by American journals, Dyar constructed the first telegraph in
America. This line, which was put up on Long Island, was of iron wire
strung on poles carrying glass insulators, and, upon it, Dyar operated
with static electricity. Causing the spark to act upon a movable disk
covered with litmus paper, he produced by the discoloration of the
latter dots and dashes that formed an alphabet.

[Illustration: FIG. 2.]

These experiments, it seems, were so successful that Dyar and his
relatives resolved to construct a line from New York to Philadelphia;
but quarrels with his copartners, lawsuits, and other causes obliged him
to leave for Rhode Island, and finally for France in 1831. He did not
return to America till 1858.

Dyar, then, would seem to have been the first who combined an alphabet
composed of dots and dashes. On this point, priority has been claimed by
Swaim in a book that appeared at Philadelphia in 1829 under the title of
_The Mural Diagraph_, and in a communication inserted in the _Comptes
Rendus_ of the Academic des Sciences for Nov. 27, 1865.

[Illustration: FIG. 3.]

In 1828, likewise, Victor Triboaillet de Saint Amand proposed to
construct a telegraph line between Paris and Brussels. This line was to
be a subterranean one, the wire being covered with gum shellac, then
with silk, and finally with resin, and being last of all placed in glass
tubes. A strong battery was to act at a distance upon an electroscope,
and the dispatches were to be transmitted by the aid of a conventional
vocabulary based upon the number of the electroscope's motions.

Finally, in 1844, Henry Highton took out a patent in England for a
telegraph working through electricity of high tension, with the use of
a single line wire. A paper unrolled regularly between two points, and
each discharge made a small hole in it, But this hole was near one
or the other of the points according as the line was positively or
negatively charged. The combination of the holes thus traced upon two
parallel lines permitted of the formation of an alphabet. This telegraph
was tried successfully over a line ten miles long, on the London and
Northwestern Railway.

[Illustration: FIG. 4.]

We have followed electrostatic telegraphs up to an epoch at which
telegraphy had already entered upon a more practical road, and it now
remains for us to retrace our steps toward those apparatus that are
based upon the use of the voltaic current.

* * * * *

Prof. Dolbear observes that if a galvanometer is placed between the
terminals of a circuit of homogeneous iron wire and heat is applied, no
electric effect will be observed; but if the structure of the wire
is altered by alternate bending or twisting into a helix, then the
galvanometer will indicate a current. The professor employs a helix
connected with a battery, and surrounding a portion of the wire in
circuit with the galvanometer. The current in the helix magnetizes the
circuit wire inclosed, and the galvanometer exhibits the presence of
electricity. The experiment helps to prove that magnetism is connected
with some molecular change of the magnetized metal.

* * * * *




ELECTRICAL TRANSMISSION AND STORAGE.

[Footnote: From a recent lecture in London before the Institute of Civil
Engineers.]

By Dr. C. WILLIAM SIEMENS, F.R.S, Mem. Inst. C.E.


Dr. Siemens, in opening the discourse, adverted to the object the
Council had in view in organizing these occasional lectures, which were
not to be lectures upon general topics, but the outcome of such special
study and practical experience as members of the Institution had
exceptional opportunities of acquiring in the course of their
professional occupation. The subject to be dealt with during the present
session was that of electricity. Already telegraphy had been brought
forward by Mr. W. H. Preece, and telephonic communication by Sir
Frederick Bramwell.

Thus far electricity had been introduced as the swift and subtile agency
by which signals were produced either by mechanical means or by the
human voice, and flashed almost instantaneously to distances which were
limited, with regard to the former, by restrictions imposed by the
globe. To the speaker had been assigned the task of introducing to their
notice electric energy in a different aspect. Although still giving
evidence of swiftness and precision, the effects he should dwell upon
were no longer such as could be perceived only through the most delicate
instruments human ingenuity could contrive, but were capable of rivaling
the steam engine, compressed air, and the hydraulic accumulator in the
accomplishment of actual work.

In the early attempts at magneto electric machines, it was shown that,
so long as their effect depended upon the oxidation of zinc in a
battery, no commercially useful results could have been anticipated. The
thermo-battery, the discovery of Seebeck in 1822, was alluded to as a
means of converting heat into electric energy in the most direct manner;
but this conversion could not be an entire one, because the second law
of thermo-dynamics, which prevented the realization as mechanical force
of more than one seventh part of the heat energy produced in combustion
under the boiler, applied equally to the thermo-electric battery, in
which the heat, conducted from the hot points of juncture to the
cold, constituted a formidable loss. The electromotive force of each
thermo-electric element did not exceed 0.036 of a volt, and 1,800
elements were therefore necessary to work an incandescence lamp.

A most useful application of the thermo-electric battery for measuring
radiant heat, the thermo pile, was exhibited. By means of an ingenious
modification of the electrical pyrometer, named the bolometer, valuable
researches in measuring solar radiations had been made by Professor
Langley.

Faraday's great discovery of magneto-induction was next noticed, and the
original instrument by which he had elicited the first electric spark
before the members of the Royal Institution in 1831, was shown in
operation. It was proved that although the individual current produced
by magnetoinduction was exceedingly small and momentary in action, it
was capable of unlimited multiplication by mechanical arrangements of a
simple kind, and that by such multiplication the powerful effects of the
dynamo machine of the present day were built up. One of the means for
accomplishing such multiplication was the Siemens armature of 1856.
Another step of importance was that involved in the Pacinotti ring,
known in its practical application as the machine of Gramme. A third
step, that of the self exciting principle, was first communicated by Dr.
Werner Siemens to the Berlin Academy, on the 17th of January, 1867, and
by the lecturer to the Royal Society, on the 4th of the following
month. This was read on the 14th of February, when the late Sir Charles
Wheatstone also brought forward a paper embodying the same principle.
The lecturer's machine, which was then exhibited, and which might be
looked upon as the first of its kind, was shown in operation; it had
done useful work for many years as a means of exciting steel magnets.
A suggestion contained in Sir Charles Wheatstone's paper, that "a very
remarkable increase of all the effects, accompanied by a diminution in
the resistance of the machine, is observed when a cross wire is placed
so as to divert a great portion of the current from the electro-magnet,"
had led the lecturer to an investigation read before the Royal Society
on the 4th of March, 1880, in which it was shown that by augmenting the
resistance upon the electro-magnets 100 fold, valuable effects could be
realized, as illustrated graphically by means of a diagram. The most
important of these results consisted in this, that the electromotive
force produced in a "shunt-wound machine," as it was called, increased
with the external resistance, whereby the great fluctuations formerly
inseparable from electric arc lighting could be obviated, and thus,
by the double means of exciting the electro-magnets, still greater
uniformity of current was attainable.

The conditions upon which the working of a well conceived dynamo machine
must depend were next alluded to, and it was demonstrated that when
losses by unnecessary wire resistance, by Foucault currents, and by
induced currents in the rotating armature were avoided, as much as 90
per cent., or even more, of the power communicated to the machine was
realized in the form of electric energy, and that _vice versa_ the
reconversion of electric into mechanical energy could be accomplished
with similarly small loss. Thus, by means of two machines at a moderate
distance apart, nearly 80 per cent, of the power imparted to one machine
could be again yielded in the mechanical form by the second, leaving
out of consideration frictional losses, which latter need not be
great, considering that a dynamo machine had only one moving part
well balanced, and was acted upon along its entire circumference by
propelling force. Jacobi had proved, many years ago, that the maximum
efficiency of a magneto-electric engine was obtained when

e / E = w / W = 1/2

which law had been frequently construed, by Verdet (Theorie Mecanique
de la Chaleur) and others, to mean that one-half was the maximum
theoretical efficiency obtainable in electric transmission of power, and
that one half of the current must be necessarily wasted or turned into
heat. The lecturer could never be reconciled to a law necessitating such
a waste of energy, and had maintained, without disputing the accuracy of
Jacobi's law, that it had reference really to the condition of maximum
work accomplished with a given machine, whereas its efficiency must be
governed by the equation:

e / E = w / W = nearly 1

From this it followed that the maximum yield was obtained when two
dynamo machines (of similar construction) rotated nearly at the same
speed, but that under these conditions the amount of force transmitted
was a minimum. Practically the best condition of working consisted in
giving to the primary machine such proportions as to produce a current
of the same magnitude, but of 50 per cent, greater electromotive force
than the secondary; by adopting such an arrangement, as much as 50 per
cent, of the power imparted to the primary could be practically received
from the secondary machine at a distance of several miles. Professor
Silvanus Thompson, in his recent Cantor Lectures, had shown an ingenious
graphical method of proving these important fundamental laws.

The possibility of transmitting power electrically was so obvious that
suggestions to that effect had been frequently made since the days of
Volta, by Ritchie, Jacobi, Henry, Page, Hjorth, and others; but it
was only in recent years that such transmission had been rendered
practically feasible.

Just six years ago, when delivering his presidential address to the Iron
and Steel Institute, the lecturer had ventured to suggest that "time
will probably reveal to us effectual means of carrying power to great
distances, but I cannot refrain from alluding to one which is, in my
opinion, worthy of consideration, namely, the electrical conductor.
Suppose water power to be employed to give motion to a dynamo-electrical
machine, a very powerful electrical current will be the result, which
may be carried to a great distance, through a large metallic conductor,
and then be made to impart motion to electromagnetic engines, to ignite
the carbon points of electric lamps, or to effect the separation of
metals from their combinations. A copper rod 3 in. in diameter would
be capable of transmitting 1,000 horse power a distance of say thirty
miles, an amount sufficient to supply one-quarter of a million candle
power, which would suffice to illuminate a moderately-sized town." This
suggestion had been much criticised at the time, when it was still
thought that electricity was incapable of being massed so as to deal
with many horse power of effect, and the size of conductor he had
proposed was also considered wholly inadequate. It would be interesting
to test this early calculation by recent experience. Mr. Marcel Deprez
had, it was well known, lately succeeded in transmitting as much as
three horse power to a distance of 40 kilometers (25 miles) through
a pair of ordinary telegraph wires of 4 millimeters in diameter. The
results so obtained had been carefully noted by Mr. Tresca, and had been
communicated a fortnight ago to the French Academy of Sciences. Taking
the relative conductivity of iron wire employed by Deprez, and the 3
in. rod proposed by the lecturer, the amount of power that could be
transmitted through the latter would be about 4,000 horse power. But
Deprez had employed a motor-dynamo of 2,000 volts, and was contented
with a yield of 32 per cent. only of the energy imparted to the primary
machine, whereas he had calculated at the time upon an electromotive
force of 200 volts, and upon a return of at least 40 per cent. of the
energy imparted. In March, 1878, when delivering one of the Science
Lectures at Glasgow, he said that a 2 in. rod could be made to
accomplish the object proposed, because he had by that time conceived
the possibility of employing a current of at least 500 volts. Sir
William Thomson had at once accepted these views, and with the
conceptive ingenuity peculiar to himself, had gone far beyond him, in
showing before the Parliamentary Electric Light Committee of 1879, that
through a copper wire of only 1/2 in. diameter, 21,000 horse power might
be conveyed to a distance of 300 miles with a current of an intensity
of 80,000 volts. The time might come when such a current could be dealt
with, having a striking distance of about 12 ft. in air, but then,
probably, a very practical law enunciated by Sir William Thomson would
be infringed. This was to the effect that electricity was conveyed at
the cheapest rate through a conductor, the cost of which was such
that the annual interest upon the money expended equaled the annual
expenditure for lost effect in the conductor in producing the power to
be conveyed. It appeared that Mr. Deprez had not followed this law in
making his recent installations.

Sir William Armstrong was probably first to take practical, advantage of
these suggestions in lighting his house at Cragside during night time,
and working his lathe and saw bench during the day, by power transmitted
through a wire from a waterfall nearly a mile distant from his mansion.
The lecturer had also accomplished the several objects of pumping water,
cutting wood, hay, and swedes, of lighting his house, and of carrying on
experiments in electro-horticulture from a common center of steam power.
The results had been most satisfactory; the whole of the management
had been in the hands of a gardener and of laborers, who were without
previous knowledge of electricity, and the only repairs that had been
found necessary were one renewal of the commutators and an occasional
change of metallic contact brushes.

An interesting application of electric transmission to cranes, by Dr.
Hopkinson, was shown in operation.

Among the numerous other applications of the electrical transmission
of power, that to electrical railways, first exhibited by Dr. Werner
Siemens, at the Berlin Exhibition of 1879, had created more than
ordinary public attention. In it the current produced by the dynamo
machine, fixed at a convenient station and driven by a steam engine
or other motor, was conveyed to a dynamo placed upon the moving car,
through a central rail supported upon insulating blocks of wood, the two
working rails serving to convey the return current. The line was 900
yards long, of 2 ft gauge, and the moving car served its purpose of
carrying twenty visitors through the exhibition each trip. The success
of this experiment soon led to the laying of the Lichterfelde line, in
which both rails were placed upon insulating sleepers, so that the one
served for the conveyance of the current from the power station to the
moving car, and the other for completing the return circuit. This line
had a gauge of 3 ft. 3 in., was 2,500 yards in length, and was worked
by two dynamo machines, developing an aggregate current of 9,000 watts,
equal to 12 horse power. It had now been in constant operation since May
16, 1881, and had never failed in accomplishing its daily traffic.
A line half a kilometer in length, but of 4 ft. 81/2 in. gauge was
established by the lecturer at Paris in connection with the Electric
Exhibition of 1881. In this case, two suspended conductors in the form
of hollow tubes with a longitudinal slit were adopted, the contact being
made by metallic bolts drawn through these slit tubes, and connected
with the dynamo machine on the moving car by copper ropes passing
through the roof. On this line 95,000 passengers were conveyed within
the short period of seven weeks.

An electric tramway, six miles in length, had just been completed,
connecting Portrush with Bush Mills, in the north of Ireland, in the
installation of which the lecturer was aided by Mr. Traill, as engineer
of the company by Mr. Alexander Siemens, and by Dr. E. Hopkinson,
representing his firm. In this instance the two rails, 3 ft. apart, were
not insulated from the ground, but were joined electrically by means of


 


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