each. The number of establishments at which the process is in operation is about 15, and the number of converters employed upwards of 50. The chief market is for rails, and a large proportion of the orders are for American roads. In England, not much ordinary line has been laid with steel rails, but on most roads those portions which are exposed to excessive wear, such as stations and inclines, are being relaid with steel. The public are already familiar with the vastly superior endurance of steel in such situations, and nothing need therefore be said here on that point.

MANUFACTURE OF STEEL RAILS.

It is usual, as already stated, to cast a 10-inch square ingot for rails. At most works, this is heated in a reverberatory furnace and hammered down to 7 inches square. At some prominent establishments, however, this process is dispensed with, and a 10-inch ingot is taken directly to the rolls and rolled down to 7 inches. At Crewe, Mr. Ramsbottom employs a heavy cogging machine for the same purpose. This is simply a form of reversing rolls made exceedingly large, and only performing a part of a revolution at each pass of the ingot. It is stated that the rails made from unhammered ingots stand equally good tests with those which have first undergone hammering.

The substitution of rolling of course cheapens the manufacture and reduces the amount of plant necessary, as well as the number of hands required. It is usual after the ingot has been brought from 10 inches down to 7 inches to put it back into the heating furnace for a short time, to bring it up to a heat sufficient to carry it through the remainder of the process. With hammered ingots it is usual to allow them to become cold after hammering, and to reheat them entirely anew, since it is not easy to regulate the heats so as to have the hammer supply hot ingots to the furnaces for the rolling mill. This, of course, involves a further additional expense in the use of the hammer. In heating the ingots care has to be taken that the heat is not forced so as to burn the steel, and ample time must be given for it to "soak." Practically about four heats are obtained in twelve hours, where with iron seven or eight could be got. When the ingots are rolled from the cast size it is usual to provide larger furnaces and a greater number for the first heat than for the second, as the fewer and smaller ones will work off the same number of ingots, on account of the shorter time necessary to bring them to the required heat. At the Dowlais works, for example, there are seven furnaces holding seven ingots each for the first heat, and but four holding four apiece for the supplementary heating.

The usual size of rolls for steel rails of the English (80 lbs per yard) or other pattern is from 22 inches to 24 inches diameter. In some cases, however, smaller sizes are in use, as at Crewe, and at the Mersey iron and steel works, at the latter of which only an 18-inch train is employed. These, however, are trains which were originally intended for rolling iron rails, and have been compelled to do service for steel.

The speed with rolls of the first mentioned sizes varies from sixty to forty revolutions per minute; the former extreme, however, seems preferable. The drafts on the rolls are made somewhat lighter and more numerous than for iron-say two more grooves for finishing.

At several works reversing rolling mills have been erected, to avoid the necessity of lifting the ingots in returning, and also to save time by operating on the ingot when moving in either direction. The usual plan has been to effect the reversing by engaging by means of a clutch gears running in opposite directions. This necessarily brings a severe shock on all the machinery, especially at high speeds, and in some cases where the arrangement has been introduced it is not used, the mill always running in one direction, and the rolling being carried on in the usual

Mr. Ramsbottom has constructed and patented a reversing mill, which he uses for rolling locomotive frame plates, at Crewe, which is free from this objection. He drives his rolls by a pair of engines, resembling a set of locomotive engines in most of their details, and without any fly-wheel. These work at a high speed, and are geared to the rolls in such a manner as to reduce the speed to the required amount. The link motion is thrown up or down in reversing by a hydraulic piston, easily set in motion by the attendant, and by these means the engines can be reversed seventy times per minute and entirely without shock. This principle for reversing would appear much preferable to the use of a clutch. The employment of a fly-wheel is not found necessary, as the engines, in virtue of their high speed, contain power sufficient to overcome any obstacles within the limits of safety to the rolls, beyond which it is better that they should stop. Mr. Ramsbottom has adopted in this set of rolls a thorough application of hydraulic power for all the operations of manipulation, and has thereby obtained great facility of working and economy of labor. Instead of the reversing principle, a steam or hydraulic lifting gear is used at some works for raising the ingot to the level of the top of the upper roll, and by many this is preferred to reversing.

The Siemens furnace is coming extensively into use in steel works for heating ingots. At present they are in operation at Crewe, Bolton, Barrow, the Mersey works, and some other places. They require a certain amount of care in their management, but yield very satisfactory results in their working. They are expensive in first cost, but in districts where coal slack is abundant they are exceedingly economical in respect of fuel, since they allow of the use of this cheap material instead of better and more expensive coal. But even where good coal must be employed in the gas producers, the utilization of all the heat produced by combustion renders the saving of fuel very considerable as compared with the ordinary reverberatory furnace. For steel an excessively high temperature, such as is required for some operations, and which alone. the Siemens regenerators are able to give, is not necessary, and where much steam power is required it may be quite as economical to employ

the waste heat from the furnaces for heating the boilers as to pass it through regenerators for the purpose of heating the incoming gases for the furnaces themselves. In such a case as much and more expensive fuel might be required for generating steam under independent boilers as would be saved at the furnaces by the use of the regenerators. In this connection may be noticed a plan that has been adopted at the Bolton works with good results, viz: the heating of boilers by gas drawn directly from the gas producers. This, of course, gives the same economy in respect of the use of slack as already referred to. Where sufficient steam is already obtained or is not required at all, the regenerative furnaces are of undoubted advantage. Mr. Webb, at Bolton, states that it is still an open question with him whether it is preferable to heat his boilers, as already mentioned, by gas, or to place them over furnaces fired in the ordinary way with coal.

The sawing, straightening, and punching of rails are conducted in general as in America, with the exception that a single saw, or a pair side by side, instead of two separated by the length of the rail, is used. The length of the rail is regulated by stops on the carriage, one end being sawed off and the rail then passed along on the friction-rollers in the carriage till it reaches the stop, when the other end is cut off. The use of a single saw, it is claimed, enables the cut to be made at the most suitable point, as indicated by the appearance of the end, and also gives greater facility in varying the length of the rail as required for different orders. At Barrow, the rollers in the saw carriage are driven by friction gearing from the saw engine, so that the rail is passed along automatically; the carriage is also drawn up to the saw by a number of racks and pinions at intervals along its length driven in a similar manner.

At some works severe tests are adopted for ascertaining the quality of rails, and until more accurate knowledge of the nature of the Bessemer ingots is obtained some such tests would appear to be very necessary. The usual method of procedure is to place a rail from each lot made from one mixing of metal on supports three feet apart, and let fall upon it midway between them a weight of one ton from heights varying from 10 to 30 feet, and observing the deflection produced. It is considered that good rails should not break under this test, though they may bend considerably where great height of fall is employed.

The use of steel-headed rails is a point of great importance, but one on which at present little that is conclusive can be said. They have been made to a considerable extent at the Crewe works of the London and Northwestern Railway Company for use on that line, and Mr. Webb (formerly of Crewe) has patents for forms and materials of piles for their production. One of the points which Mr. Webb claims is interposing a layer of puddle bar between the steel face and the fibrous iron, for the purpose of making a more gradual transition between the crystalline and fibrous metals, and thereby securing a more perfect union in the successive layers. The same thing has been done for many years in the United

States. In the Exposition specimens of steel-headed rails of French manufacture are shown, which have been struck on the top of the head with a steam hammer, cracking vertically through both steel and iron, and buckling up the web without any appearance of separation between the steel face and the iron beneath it. Although the specimen gives no evidence of being a selected one, (the line of the weld being plainly marked on the external surface,) yet it is clear that no such test can decide a question which can really only be properly solved by experience under the conditions of regular working. A sudden blow may be incompetent to produce effects which may follow prolonged and irregular hammering under the wheels of railway trains. While, therefore, steelheaded rails cannot be pronounced an absolute success, there is every reason for prosecuting the experiment, and reasonable grounds for anticipating a perfectly successful result.1

As the production of rails is at present the largest branch of the Bessemer steel manufacture, the disposition to be made of the crop ends becomes a question of immediate importance, and that to be made of the worn-out rails one of future moment. As the metal, when it contains any material proportion of carbon, is unreliable when welded, it is not so easy to decide to what use the large amount of ends sawed off from the rails shall be put. At present it must be admitted they are rather a drug in the market. When an iron that works hot in the converter is used, a certain quantity of these ends may be remelted in the vessel without injury to the steel. About four hundred weight per charge of five tons is considered admissible at the Dowlais works, the scrap being first heated to a red heat in a furnace placed near the vessel, and thrown into the latter before running in the molten iron. It is difficult, however, to dispose of the whole amount in this way. As large a portion as possible is sold to the Sheffield crucible steel makers, who remelt them, and sell them at a greatly advanced price. At some works, again, they are rolled into small plates, and in this form they may be used for the manufacture of plough shares and other kindred objects; or in some cases they may be rolled and drawn into telegraph wire; it would be impossible, however, to make fine sizes of wire from them. If the difficulty of disposing of the steel scrap is to continue, it forms another argument in favor of steel-headed rails, since these, when worn out, would contain but little steel and could be readily piled and rerolled, the pile being so arranged as to bring the steel in the least vital parts of the rail in case its presence should lead to any unsoundness of the welding. It would appear, however, that an adequate market for old rails could be formed by rerolling them into the form of bars for machinery and other purposes, for which, by reason of their superior strength, they should be more valuable than wrought iron.

Experiments made in the United States, after a trial of two years, have demonstrated that a perfectly sound weld of the steel to the iron can be secured in the head of the rail.

MANUFACTURE OF TIRES.

Next in importance to the manufacture of steel rails is that of tires for locomotive and railway carriage wheels. Four years ago it was attempted to weld these up, as in the case of iron from straight bars, but the unreliability of all tires so made was soon apparent, and the attention of manufacturers was directed to discovering some practicable means of producing them without welds. With the exception of the form of the ingot cast for the purpose, the mode of manufacture adopted at all the English works has attained a remarkable degree of uniformity. Mr. Ramsbottom casts his tire ingots in the form of a truncated cone, a usual size being two feet diameter at the bottom, six inches diameter at the top, and thirty inches height. This he hammers on its ends and sides till it assumes the shape of an ordinary flat cheese, with a thickness of about twelve inches. Another heat is then taken on it, and it is then placed under a steam hammer furnished with a pointed conical tool, and by successive blows with this on both sides a hole is forced through the centre of the disk, and this again expanded as the hammering proceeds, till the upper part of the tool, which is flat, comes down upon the tire and consolidates the metal by reducing its thickness. A third heat is then taken, and the ring so formed is placed over a stout beck projecting from the inclined side of an anvil, which maintains the ring in such a position as to give a suitable bevel to the outer face when struck by the hammer, while at the same time its diameter is considerably increased by the operation. After this third hammering it is ready for the rolls, and a fourth and last heat is taken for that purpose. Mr. Ramsbottom holds a patent for the method of punching the tire blocks by a sharp-pointed conical tool without the removal of any of the metal. The form of rolling mill employed by Mr. Ramsbottom is exceedingly complicated, and is the only one of its kind, as far as the writer is aware, which is in use in England, unless it be at the works of the patentee, Mr. Jackson, at Manchester.

At Mr. Allen's works, Sheffield, (H. Besse.ner & Co.,) the cheese-shaped blocks are produced from an ingot of the ordinary square form, this being cast sufficiently large to form a number of tires, say four, and then hammered round and cut up into sections, each of a weight suitable for one tire. The central hole is punched by flat-ended punches about eight inches in diameter at the lower end, and perhaps nine inches above, driven in from both sides successively, and knocking out a circular disk about two inches thick as scrap. The blocks used with this process are of less thickness, say seven inches. The hole so formed is slightly enlarged by forcing the ring down over a truncated conical block which is placed on the anvil for the purpose, and subsequently another heat is taken, and the hammering continued on the inclined back of an anvil, as already described. The weight of the block can be accurately adjusted by varying the thickness at the time of punching out the central