The manufacture of steel rails, carried on first at Terni and afterwards at Savona, began in Italy in 1886.
Rails placed on the bridge girders.
It is practically a traveller mounted on high legs, so as to permit of its being travelled on rails placed on the ground level, instead of on an elevated gantry.
4), pigeons, gulls, plovers, rails and penguins, have the vomer pointed in front while the maxillo-palatines are free, leaving a fissure between the vomer and themselves.
Zealand parrot, Stringops, less in various flightless rails, in the dodo and solitaire.
In the Cathartae, in the Anseres, gulls, rails and various other aquatic birds.
Gallinaceous birds, storkand crane-like waders, rails, birds of prey, cormorants, &c. Especially numerous bones have been found in the Paris basin, chiefly described by G.
New Zealand has also yielded many flightless birds, notably the numerous species and genera of Dinornithidae, some of which survived into the 19th century; Pseudapteryx allied to the Kiwi; Cnemiornis, a big, flightless goose; Aptornis and Notornis, flightless rails; and Harpagornis, a truly gigantic bird of prey with tremendous wings and talons.
So intensely aristocratic (hence his nickname 6 AoXoiSopos, "he who rails at the people") was his temperament that he declined to exercise the regal-hieratic office of 1 3avLAeus which was hereditary in his family, and presented it to his brother.
" The manner of the carriage," says Lord Keeper North in 1676, " is by laying rails of timber.
But the iron sheathing was not strong enough to resist buckling under the passage of the loaded wagons, and to remedy this defect the plan, was tried of making the rails wholly of iron.
In 1767 the Colebrookdale Iron Works cast a batch of iron rails or plates, each 3 ft.
This line was originally designed as a " plateway " on the Outram system, but objections were raised to rails with upstanding ledges or flanges FIG.
This method, however, was not found satisfactory: the projecting feet were liable to be broken off, and in 1799 or 1800 Jessop abandoned them, using instead separate cast-iron sockets or chairs, which were fastened to the sleepers and in which the rails were supported in an upright position.
The manufacture of the rails themselves was gradually improved.
By making them in longer lengths a reduction was effected in the number of joints - always the weakest part of the line; and another advance consisted in the substitution of wrought iron for cast iron, though that material did not gain wide adoption until after the patent for an improved method of rolling rails granted in 1820 to John Birkinshaw, of the Bedlington Ironworks, Durham.
His rails were wedge-shaped in section, much wider at the top than at the bottom, with the intermediate portion or web thinner still, and he recommended that they should be made 18 ft.
The fishbellied rails, however, were found to break near the chairs, and from 1834 they began to be replaced with parallel rails weighing 50 lb to the yard.
3); he had to get the first lot of these rails, which were 15 ft.
There was a waste of metal in these early rails owing to the excessive thickness of the vertical web, and subsequent improvements have consisted in adjusting the dimensions so as to combine strength with economy of metal, as well as in the substitution of steel for wrought iron (after the introduction of the Bessemer process) and in minute attention to the composition of the steel employed.
Bridges Adams, the intention being by " fishing " the joints to convert the rails into continuous beams. In the original design two chairs were placed, one under each rail, a few inches apart, as in fig.
The joint was thus suspended between the two chairs, and two keys of iron, called " fishes," fitting the side channels of the rails, were driven in on each side between the chairs and the rails.
In subsequent modifications the fishes were, as they continue to be, bolted to and through the rails, the sleepers being placed rather further apart and the joint being generally suspended between them.
Thus it may fairly be said that the railway system of the United States was reconstructed between 1896 and 1905, so far as concerns rails, sleepers, ballast and the general capacity of a given group of lines to perform work.
The act of 1871 further renders it obligatory upon every railway company to send notice to the Board of Trade in the case of (1) any accident attended with loss of life or personal injury to any person whatsoever; (2) any collision where one of the trains is a passenger train; (3) any passenger train or part of such train leaving the rails; (4) any other accident likely to have caused loss of life or personal injury, and specified on that ground by any order made from time to time by the Board of Trade.
From the falling of rails, sleepers, &c., when at work on the line .
Passenger trains or parts of passenger trains leaving the rails 8.
Goods trains or parts of goods trains, lightengines, &c., leaving the rails 9.
The theoretical limit is about i in 16; between I in 20 and 1 in 16 a steam locomotive depending on the adhesion between its wheels and the rails can only haul about its own weight.
Blenkinsop placed the teeth on the outer side of one of the running rails, and his reason for adopting a rack was the belief that an engine with smooth wheels running on smooth rails would not have sufficient adhesion to draw the load required.
Two lines may be drawn from this point, one to each of the two rails, in a plane normal to the rails, and the ends of these lines, where they meet the rails, may be joined to complete a triangle, which may conveniently be regarded as a rigid frame resting on the rails.
If therefore the outer rail is laid at a level above that of the inner rail at the curve, overturning will be resisted more than would be the case if both rails were in the same horizontal plane, since the tilting of the vehicle due to this " superelevation " diminishes the overturning moment, and also increases the restoring moment, by shortening in the one case and lengthening in the other the lever arms at which the respective forces act.
The amount of superelevation required to prevent derailment at a curve can be calculated under perfect running conditions, given the radius of curvature, the weight of the vehicle, the height of the centre of gravity, the distance between the rails, and the speed; but great experience 1 See The Times Engineering Supplement (August 22, 1906), p. 265.
Closely allied to the question of safety is the problem of preventing jolting at curves; and to obtain easy running it is necessary not merely to adjust the levels of the rails in respect to one another, but to tail off one curve into the next in such a :nanner as to avoid any approach to abrupt lateral changes of direction.
The gauge of a railway is the distance between the inner edges of the two rails upon which the wheels run.
Sleepers, called ties or cross-ties in America, are the blocks or slabs on which the rails are carried.
There are two main ways of attaching the rails to the sleepers, corresponding to two main types of rails - the bull-headed rail A B FIG.
Some extent in France and India, the rails have rounded bases and are supported by being wedged, with wooden keys, in castiron chairs which are bolted to the sleepers.
The keys which hold the rail in the chairs are usually of oak and are placed outside the rails; the inside position has also been employed, but has the disadvantage of detracting from the elasticity of the road since the weight of a passing train presses the rails up against a rigid mass of metal instead of against a slightly yielding block of wood.
The rails, which for heavy main line traffic may weigh as much as too lb per yard, or even more, are rolled in lengths of from 30 to 60 ft., and sleepers are placed under them at intervals of between 2 and 3 ft.
Preferably, they are so arranged that those in both lines of rails come opposite each other and are placed between the same pair of sleepers.
Flat-bottomed rails are fastened to the sleepers by hookheaded spikes, the heads of which project over the flanges.
In the United States the spikes are simply driven in with a maul, and the rails stand upright, little care being taken to prepare seats for them on the sleepers, on which they soon seat themselves.
The joints of flanged rails are similar to those employed with bull-headed rails.
The substitution of steel for iron as the material for rails which made possible the axle loads and the speeds of Lto-day, and, by reducing the cost of maintenance, contributed enormously to the economic efficiency of railways, was one of the most important events in the history of railways, and a scarcely less important element of progressive economy has been the continued improvement of the steel rail in stiffness of section and in toughness and hardness of material.
The specifications for bull-headed rails issued by the British Engineering Standards Committee in 1904 provided for a carbon-content ranging from 0-35 to 0-50%, with a phosphorus maximum of 0.075%.
In the United States a committee of the American Society of Civil Engineers, appointed to consider the question of rail manufacture in consequence of an increase in the number of rail-failures, issued an interim report in 1907 in which it suggested a range of carbon from 0-55 to 0-65% for the heaviest sections of Bessemer steel flange rails, with a phosphorus maximum of 0.085%; while the specifications of the American Society for Testing Materials, current at the same period, put the carbon limits at o 45 to 0-55%, and the phosphorus limit at o io.
For rails of basic open-hearth steel, which is rapidly ousting Bessemer steel, the Civil Engineers' specifications allowed from o 65 to 0-75% of carbon with 0-05% of phosphorus, while the specifications of the American Railway Engineering and Maintenance of Way Association provided for a range of 0.75 to 0-85% of carbon, with a maximum of 0.03% of phosphorus.
The standard specification adopted by the Pennsylvania railway in 1908 provided that in rails weighing Ioo lb to the yard 41% of the metal should be in the head, 18-6% in the web, and 40-4% in the base, while for 85 lb rails 42.2% was to be in the head, 17-8% in the web and 40.0% in the base.
According to the specification for 85 lb rails adopted by the Canadian Pacific railway about the same time, 36-77% of the metal was to be in the head, 22'21% in the web and 41 02% in the base.
To enable trains to be transferred from one pair of rails to another pair, as from the main line to a siding, " points " or " switches " are provided.
At the place where the four rails come together, the two inner ones (one of the main line and the other of the siding), known as " switch rails " (b, fig.
Where, as at a double-line junction, one pair of rails crosses another pair, " diamond " crossings (p) are formed.
I had to feel for the rails with my toe; but I was not afraid, and got on very well, until all at once there came a faint "puff, puff" from the distance.
If we do not get out sleepers, and forge rails, and devote days and nights to the work, but go to tinkering upon our lives to improve them, who will build railroads?
The rails are laid on them, and they are covered with sand, and the cars run smoothly over them.
Looking down over the rails Prince Nesvitski saw the rapid, noisy little waves of the Enns, which rippling and eddying round the piles of the bridge chased each other along.
He stood looking about him, when suddenly he heard a rattle on the bridge as if nuts were being spilt, and the hussar nearest to him fell against the rails with a groan.
These temporary aims are like the broom fixed in front of a locomotive to clear the snow from the rails in front: they clear men's moral responsibilities from their path.
These rails were to be rolled in 33-ft.