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

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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.

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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 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 102 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.



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.



The barrel contains 225 tubes 1.97 in. in diameter outside and 13 ft. 9 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 15 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.

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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.

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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, Chte 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 Chte 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 Chte 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.



The Grenville Canal (around the Longue Sault) with seven locks, and the Chte 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 Chte 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 Chte 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 Chte 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 1 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 1 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 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.



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.



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.



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.

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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 50 to 150 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.

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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



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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, 10x10 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.



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.



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THE HISTORY OF THE ELECTRIC TELEGRAPH.

[Footnote: Aug. Guerout in La Lurmire 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 Academic, 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 Abb 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 clat 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.



"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 fr 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 ber 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.



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.



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.

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