Chapter 4

One mile of this railway, 16 in. gauge and 9 lb. steel rail, with sixteen wagons, each having a double equilibrium tipping box containing 11 cubic feet, and all accessories, represents a weight of 20 tons--a very light weight, if it is considered that all the materials are entirely of metal. Its net cost price per mile is 450_l_., the wagons included.

Large contracts for earthwork with horse haulage are carried on to the greatest advantage with the railway of 20 in. gauge and 14 lb. rails. The length of 16 ft. 5 in. of this railway weighs 170 lb., and so can easily be carried by two men, one placing himself at each end. The wagons most in use for these works are those with double equilibrium tipping boxes, holding 18 cubic feet. These are at present employed in one of the greatest undertakings of the age, namely, the cutting of the Panama Canal, where there are used upward of 2,700 such wagons, and more than 35 miles of track.

A mile of these rails of 20 in. gauge with 14 lb. rails, together with sixteen wagons of 18 cubic feet capacity, with appurtenances, costs about 660_1_., and represents a total weight of 33 tons.

This description of material is used for all contracts exceeding 20,000 cubic yards.

A very curious and interesting use of the narrow-gauge line, and the wagons with double equilibrium tipping-box, was made by the Societe des Chemins de Fer Sous-Marins on the proposed tunnel between France and England. The line used is that of 16 in. gauge, with 9 lb. rails.

The first level of the tunnel, which was constructed by means of a special machine by Colonel Beaumont, had only a diameter of 2.13 m. (7 ft.); the tipping boxes have therefore a breadth of only 2 ft., and contain 7¼ cubic feet. The boxes are perfectly balanced, and are most easily emptied. The wagons run on two lines, the one being for the loaded trains, and the other for the empty trains.

The engineers and inspectors, in the discharge of their duties, make use of the Liliputian carriages. The feet of the travelers go between the wheels, and are nearly on a level with the rails; nevertheless, they are tolerably comfortable. They are certainly the smallest carriages for passengers that have ever been built; and the builder even prophesies that these will be the first to enter into England through the Channel Tunnel.

One of the most important uses to which a narrow gauge line can be put is that of a military railway. The Dutch, Russian, and French Governments have tried it for the transporting of provisions, of war material, and of the wounded in their recent campaigns. In Sumatra, in Turkestan, and in Tunis these military railroads have excited much interest, and have so fully established their value that this paper may confine itself to a short description.

The campaign of the Russians against the Turcomans presented two great difficulties; these were the questions of crossing districts in which water was extremely scarce or failed entirely, and of victualing the expeditionary forces. This latter object was completely effected by means of 67 miles of railway, 20 in. gauge, 14 lb. steel rails, with 500 carriages for food, water, and passengers. The rails were laid simply on the sand, so that small locomotives could not be used, and were obliged to be replaced by Kirghiz horses, which drew with ease from 1,800 lb. to 2,200 lb. weight for 25 miles per day.

In the Tunisian war this railroad of 20 in. gauge, 14 lb. rail, was replaced by that of two ft. gauge, with 14 lb. and 19 lb. rails. There were quite as great difficulties as in the Turcoman campaign, and the country to be crossed was entirely unknown. The observations made before the war spoke of a flat and sandy country. In reality a more uneven country could not be imagined; alternating slopes of about 1 in 10 continually succeeded each other; and before reaching Kairouan 7½ miles of swamp had to be crossed. Nevertheless the horses harnessed to the railway carriages did on an average twelve to seventeen times the work of those working ordinary carriages. In that campaign also, on account of the steep ascents, the use of locomotives had to be given up. The track served not only for the conveying of victuals, war material, and cannon, but also of the wounded; and a large number of the survivors of this campaign owe their lives to this railway, which supplied the means of their speedy removal without great suffering from the temporary hospitals, and of carrying the wounded to places where more care could be bestowed upon them.

The carriages which did duty in this campaign are wagons with a platform entirely of metal, resting upon eight wheels. The platform is 13 ft. 1 in. in length, and 3 ft. 11 in. in width. The total length with buffers is 14 ft. 9 in. This carriage may be at will turned into a goods wagon or a passenger carriage for sixteen persons, with seats back to back, or an ambulance wagon for eight wounded persons.

For the transport of cannon the French military engineers have adopted small trucks. A complete equipage, capable of carrying guns weighing from 3 to 9 tons, is composed of trucks with two or three axles, each being fitted with a pivot support, by means of which it is made possible to turn the trucks, with the heaviest pieces of ordnance, on turntables, and to push them forward without going off the rails at the curves.

The trucks which have been adopted for the service of the new forts in Paris are drawn by six men, three of whom are stationed at each end of the gun, and these are capable of moving with the greatest ease guns weighing 9 tons.

The narrow-gauge railway was tested during the war in Tunis more than in any preceding campaign, and the military authorities decided, after peace had been restored in that country, to continue maintaining the narrow-gauge railways permanently; this is a satisfactory proof of their having rendered good service. The line from Sousse to Kairouan is still open to regular traffic. In January, 1883, an express was established, which leaves Sousse every morning and arrives at Kairouan--a distance of forty miles--in five hours, by means of regularly organized relays. The number of carriages and trucks for the transport of passengers and goods is 118.

The success thus attained by the narrow-gauge line goes far to prove how unfounded is the judgment pronounced by those who hold that light railways will never suffice for continuous traffic. These opinions are based on certain cases in the colonies, where it was thought fit to adopt a light rail weighing about 18 lb. to 27 lb. per yard, and keeping the old normal gauge. It is nevertheless evident that it is impossible to construct cheap railways on the normal gauge system, as the maintenance of such would-be light railways is in proportion far more costly than that of standard railways.

The narrow gauge is entirely in its right place in countries where, as notably in the case of the colonies, the traffic is not sufficiently extensive to warrant the capitalization of the expenses of construction of a normal gauge railway.

Quite recently the Eastern Railway Company of the province of Buenos Ayres have adopted the narrow gauge for connecting two of their stations, the gauge being 24 in. and the weight of the rails 19 lb. per yard. This company have constructed altogether six miles of narrow-gauge road, with a rolling stock of thirty passenger carriages and goods trucks and two engines, at a net cost price of 7,500l., the engines included. This line works as regularly as the main line with which it is connected. The composite carriages in use leave nothing to be desired with regard to their appearance and the comforts they offer. Third-class carriages, covered and open, and covered goods wagons, are also employed.

All these carriages are constructed according to the model of those of the Festiniog Railway. The engines weigh 4 tons, and run at 12½ miles per hour for express trains with a live load of 16 tons; while for goods trains carrying 35 tons the rate is 7½ miles an hour.

Another purpose for which the narrow-gauge road is of the highest importance in colonial commerce is the transport of sugar cane. There are two systems in use for the service of sugar plantations:

1. Traction by horses, mules, or oxen.

2. Traction by steam-engine.

In the former case, the narrow gauge, 20 in. with 14 lb. rails, is used, with platform trucks and iron baskets 3 ft. 3 in. long.

The use of these wagons is particularly advantageous for clearing away the sugar cane from the fields, because, as the crop to be carried off is followed by another harvest, it is important to prevent the destructive action of the wheels of heavily laden wagons. The baskets may be made to contain as much as 1,300 lb. of cane for animal traction, and 2,000 lb. for steam traction. In those colonies where the cane is not cut up into pieces, long platform wagons are used entirely made of metal, and on eight wheels. When the traction is effected by horses or mules, a chain 14½ ft. long is used, and the animals are driven alongside the road. Oxen are harnessed to a yoke, longer by 20 in. to 24 in. than the ordinary yoke, and they are driven along on each side of the road.

On plantations where it is desirable to have passenger carriages, or where it is to be foreseen that the narrow-gauge line maybe required for the regular transport of passengers and goods, the 20 in. line is replaced by one of 24 in.

The transport of the refuse of sugar cane is effected by means of tilting basket carts; the lower part of which consists of plate iron as in earthwork wagons, while the upper part consists of an open grating, offering thus a very great holding capacity without being excessively heavy. The content of these wagons is 90 cubic feet (2,500 liters). To use it for the transport of earth, sand, or rubbish, the grating has merely to be taken off. In the case of the transport of sugar cane having to be effected by steam power, the most suitable width of road is 24 in., with 19 lb. rails; and this line should be laid down and ballasted most carefully. The cost of one mile of the 20 in. gauge road, with 14 lb. rails, thirty basket wagons, and accessories for the transport of sugar cane, is 700l., and the total weight of this plant amounts to 35 tons.

Owing to the great lightness of the portable railways, and the facility with which they can be worked, the attention of explorers has repeatedly been attracted by them. The expedition of the Ogowe in October, 1880, that of the Upper Congo in November, 1881, and the Congo mission under Savorgnan de Brazza, have all made use of the Decauville narrow-gauge railway system.

During these expeditions to Central Africa, one of the greatest obstacles to be surmounted was the transport of boats where the river ceased to be navigable; for it was then necessary to employ a great number of negroes for carrying both the boats and the luggage. The explorers were, more or less, left to the mercy of the natives, and but very slow progress could be made.

On returning from one of these expeditions in Africa, Dr. Balay and M. Mizon conceived the idea of applying to M. Decauville for advice as to whether the narrow-gauge line might not be profitably adapted for the expedition. M. Decauville proposed to them to transport their boats without taking them to pieces, or unloading them, by placing them on two pivot trollies, in the same manner as the guns are transported in fortifications and in the field. The first experiments were made at Petit-Bourg with a pleasure yacht. The hull, weighing 4 tons, was placed on two gun trollies, and was moved about easily across country by means of a portable line of 20 in. gauge, with 14 lb. rails. The length of the hull was about 45 ft., depth 6 ft. 7 in., and breadth of beam 8 ft. 2 in., that is to say, five times the width of the narrow-gauge, and notwithstanding all this the wheels never came off the line. The sections of line were taken up and replaced as the boat advanced, and a speed of 1,100 yards per hour was attained. Dr. Balay and M. Mizon declared that the result obtained exceeded by far their most sanguine hopes, because during their last voyage, the passage of the rapids had sometimes required a whole week for 1,100 yards (1 kilometer), and they considered themselves very lucky indeed if they could attain a speed of one kilometer per day. The same narrow gauge system has since been three times adopted by African explorers, on which occasions it was found that the 20 in. line, with 9 lb. or 14 lb. rails, was the most suitable for scientific expeditions of this nature.

The trucks used are of the kind usually employed for military purposes, with wheels, axles, and pivot bearings of steel; on being dismounted the bodies of the two trucks form a chest, which is bolted together and contains the wheels, axles, and other accessories. The total weight of the 135 yards of road used by Dr. Balay and M. Mizon during their first voyage was 2,900 lb., and the wagons weighed 5,000 lb. Hence the expedition had to carry a supplementary weight of 3½ tons; but at any given moment the material forming this burden became the means of transporting, in its turn, seven boats, representing a total weight of 20 tons.

It is impossible to enumerate in this paper all the various kinds of wagons and trucks suitable for the service of iron works, shipyards, mines, quarries, forests, and many other kinds of works; and we therefore limit ourselves to mentioning only a few instances which suffice to show that the narrow gauge can be applied to works of the most varied nature and under the most adverse circumstances possible.

It therefore only remains to mention the various accessories which have been invented for the purpose of completing the system. They consist of off-railers, crossings, turntables, etc.

The off railer is used for establishing a portable line, at any point, diverging to the right or left of a permanent line, and for transferring traffic to it without interruption. It consists of a miniature inclined plane, of the same height at one end as the rail, tapering off regularly by degrees toward the other end. It is only necessary to place the off-railer (which, like all the lengths of rail of this system, forms but one piece with its sleepers and fish-plates) on the fixed line, adding a curve in the direction it is intended to go, and push the wagons on to the off-railer, when they will gradually leave the fixed line and pass on the new track.

The switches consist of a rail-end 49 in. in length, which serves as a movable tongue, placed in front of a complete crossing, the rails of which have a radius of 4, 6, or 8 meters; a push with the foot suffices to alter the switch. There are four different models of crossings constructed for each radius, viz.:

1. For two tracks with symmetrical divergence.

2. For a curve to the right and a straight track.

3. For a curve to the left and a straight track.

4. For a meeting of three tracks.

When a fixed line is used, it is better to replace the movable switch by a fixed cast-iron switch, and to let the workmen who drive the wagon push it in the direction required. Planed switch tongues are also used, having the shape of those employed on the normal tracks, especially for the passage of small engines; the switches are, in this case, completed by the application of a hand lever.

The portable turntable consists of two faced plates laid over the other, one of thick sheet iron, and the other of cast iron. The sheet-iron plate is fitted with a pivot, around which the cast iron one is made to revolve; these plates may either be smooth, or grooved for the wheels. The former are used chiefly when it is required to turn wagons or trucks of light burden, or, in the case of earthworks, for trucks of moderate weight. These plates are quite portable; their weight for the 16 in. gauge does not exceed 200 lb. For engineering works a turntable plate with variable width of track has been designed, admitting of different tracks being used over the same turntable.

When turntables are required for permanent lines, and to sustain heavy burdens, turntables with a cast iron box are required, constructed on the principle of the turntables of ordinary railways. The heaviest wagons may be placed on these box turntables, without any portion suffering damage or disturbing the level of the ground. In the case of coal mines, paper mills, cow houses with permanent lines, etc., fixed plates are employed. Such plates need only be applied where the line is always wet, or in workshops where the use of turntables is not of frequent occurrence. This fixed plate is most useful in farmers' stables, as it does not present any projection which might hurt the feet of the cattle, and is easy to clean.

The only accident that can happen to the track is the breaking of a fish-plate. It happens often that the fish-plates get twisted, owing to rough handling on the part of the workmen, and break in the act of being straightened. In order to facilitate as much as possible the repairs in such cases, the fish-plates are not riveted by machinery, but by hand; and it is only necessary to cut the rivets with which the fish-plate is fastened, and remove it if broken: A drill passed through the two holes of the rail removes all burrs that may be in the way of the new rivet. No vises are required for this operation; the track to be repaired is held by two workmen at a height of about 28 in. above the ground, care being taken to let the end under repair rest on a portable anvil, which is supplied with the necessary appliances. The two fish-plates are put in their place at the same time, the second rivet being held in place with one finger, while the first is being riveted with a hammer; if it is not kept in its place in this manner it may be impossible to put it in afterward, as the blows of the hammer often cause the fish-plate to shift, and the holes in the rail are pierced with great precision to prevent there being too much clearance. No other accident need be feared with this line, and the breakage described above can easily be repaired in a few minutes without requiring any skilled workman.

The narrow-gauge system, which has recently received so great a development on the Continent, since its usefulness has been demonstrated, and the facility with which it can be applied to the most varied purposes, has not yet met in England with the same universal acceptance; and those members of this Institution who crossed the sea to go to Belgium were, perhaps, surprised to see so large a number of portable railways employed for agricultural and building purposes and for contractors' works. But in the hands of so practical a people it may be expected that the portable narrow gauge railway will soon be applied even to a larger number of purposes than is the case elsewhere.

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GERARD'S ALTERNATING CURRENT MACHINE.

The machine represented in the annexed engravings consists of a movable inductor, whose alternate poles pass in front of an armature composed of a double number of oblong and flat bobbins, that are affixed to a circle firmly connected with the frame. There is a similar circle on each side of the inductor. The armature is stationary, and the wires that start from the bobbins are connected with terminals placed upon a wooden support that surmounts the machine.

This arrangement allows of every possible grouping of the currents according to requirements. Thus, the armature may be divided into two currents, so as to allow of carbons 30 mm. in diameter being burned, or else so as to have four, eight, twelve, twenty-four, or even forty-eight distinct circuits capable of being used altogether or in part.

This machine has been studied with a view of rendering the lamps independent; and there may be produced with it, for example, a voltaic arc of an intensity of from 250 to 600 carcels for the lighting of a courtyard, or it may be used for producing arcs of less intensity for shops, or for supplying incandescent lamps. As each of the circuits is independent, it becomes easy to light or extinguish any one of the lamps at will. Since the conductors are formed of ordinary simple wires, the cost attending the installation of 12 or 24 lamps amounts to just about the same as it would in the case of a single cable.

One of the annexed cuts represents a Corliss steam engine connected directly with an alternating current machine of the system under consideration. According to the inventor, this machine is capable of supplying 1,000 lamps of a special kind, called "slide lamps," and a larger number of incandescent ones.--_Revue Industrielle_.

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AUTOMATIC FAST SPEED TELEGRAPHY.

By THEO. F. TAYLOR.

Since 1838 much has been done toward increasing the carrying capacity of a single wire. In response to your invitation I will relate my experience upon the Postal's large coppered wire, in an effort to transmit 800 words per minute over a 1,000 mile circuit, and add my mite to the vast sum of knowledge already possessed by electricians.

As an introduction, I shall mention a few historical facts, but do not propose to write in this article even a short account of the different automatic systems, and I must assume that my readers are familiar with modern automatic machines and appliances.

In 1870, upon the completion of the Automatic Company's 7 ohm wire between New York and Washington, it happened that Prof. Moses G. Farmer was in the Washington office when the first message was about to be sent, and upon being requested, he turned the "crank" and transmitted the message to New York, at the rate of 217 words per minute.

Upon his return to New York he co-operated with Mr. Prescott in experiments on W.U. wires, their object being to determine what could be done on iron wires with the Bain system. A good No. 8 wire running from New York to Boston was selected, reinsulated, well trimmed, and put in first-class electrical condition, previous to the test. The "Little" chemical paper was used.

The maximum speed attained on this wire was 65 words per minute.

About the same time George H. Grace used an electro magnet on the automatic line with such good effect that the speed on the New York-Washington circuit was increased to 450 words per minute.

Then a platina stylus or pen was substituted for the iron pen in connection with iodide paper, and the speed increased to 900 words per minute.

In 1880, upon the completion of the Rapid Company's 6 ohm wire, between New York and Boston, 1,200 words per minute were transmitted between the cities above named.

In 1882, I was employed by the Postal Telegraph Company to put the Leggo automatic system into practical shape, and, if possible, transmit 800 words per minute between New York and Chicago.

It was proposed to string a steel-copper wire, the copper on which was to weigh 500 lb. to the mile.

When complete, the wire was rather larger than No. 3, English gauge, but varied in diameter, some being as large as No. 1, and it averaged 525 lb. of copper per mile and = 1.5 ohms. The surface of this wire was, however, large.

Dr. Muirhead estimated its static capacity at about 10 M.F., which subsequent tests proved to be nearly correct.

It will be understood that this static capacity stood in the way of fast transmission.

Resistance and static capacity are the two factors that determine speed of signaling.