equal hardness in every part may be produced, without the necessity of welding or joining of separate pieces. That this can be accomplished, is shown by the specimens exhibited. The iron bars of 3 inches square, which have been bent and doubled-up cold, the twisted bars, and the collapsed cylinders which do not split, but yield like copper to the blows of the hammer, prove this. If assurance be required, that there are no hard ribs, or sand cracks, the examples of the malleable iron gun, or the iron and steel cylinders may be taken. With reference to the tensile strength of iron bars, or boiler plate, so made from English coke pig metal, the careful testing of plates made of puddled iron, according to Mr. W. Fairbairn, has given an average of 45,300 lbs. per square inch for Staffordshire plates, 45,000 lbs. for Derbyshire, and 57,120 lbs. for Yorkshire plates. Now, four samples of the Bessemer iron plate, tested at the Royal Arsenal, Woolwich, according to the report of Colonel Eardley Wilmot, gave an average of 68,314 lbs., or 63,591 lbs. as the least, and 73,100 lbs. as the highest proof for boiler plates 3/8 ths of an inch in thickness. Here, then, is a result showing a greater amount of tensile strength above Low Moor, or Bowling iron boiler plates, than those plates possess above the ordinary quality of Staffordshire plates.

Here there is proof that Bessemer iron plates, tested at Woolwich Arsenal by Sir William Armstrong's immediate predecessor in office, gave an average tensile strength of 68,314 lb. per square inch=30 1/2 tons, quite five tons over the best Yorkshire plates. Also, the fact is demonstrated that this superior iron could be made from Swedish charcoal pig iron at about one-half the cost of Yorkshire iron bars, and that it could be made with great rapidity into masses of any form of several tons in weight without welding. Again I quote from the paper:

In order to show the extreme toughness of such iron, and to what a strain it may be subjected without bursting, several cast and hammered cylinders were placed cold under the steam hammer, and were crushed down, without the least appearance of tearing the metal. Now these cylinders were drawn from a round cast-iron ingot, only 2 in. larger in diameter than the finished cylinder, and in the precise manner in which a gun should be treated. They may, therefore, be considered as short sections of an ordinary 9-pounder field gun. Iron so made requires very little forging; indeed, the mere closing of the pores of the metal seems all that is necessary. The tensile strength of the samples, as tested at the Royal Arsenal, was 64,566 lb. per square inch, while the tensile stress of pieces cut from the Mersey gun gave a mean of 50,624 lb. longitudinally, and 43,339 lb. across the grain; thus showing a mean of 17,550 lb. per square inch in favour of the Bessemer iron.

If it be desired to produce ordnance by merely founding the metal, then the ordinary casting process may be employed: with the simple difference that the iron, instead of running direct from the melting furnace into the mould, must first be run into the converting vessel, where in from ten to twenty minutes it will become steel, or malleable iron, as may be desired; and the casting may then take place in the ordinary way. The small piece of ordnance exhibited will serve to illustrate this important manufacture, and is interesting in consequence of its being the first gun that ever was made of malleable iron without a weld or joint. The importance of this fact will be much enhanced when it is known that conical masses of this pure tough metal, of from five to ten tons in weight, can be produced at Woolwich at a cost not exceeding £6 12s. 0d. per ton, inclusive of the cost of pig iron, carriage, re-melting, waste in the process, labour, and engine power.

It will be interesting to those who are watching the advancement of the new process to know that it is already rapidly extending itself over Europe. The enterprising firm of Daniel Elfstand and Company, of Edsken, who were the pioneers in Sweden, have now made several hundred tons of excellent steel by the Bessemer process. Another large works has since started in their immediate neighbourhood, and two other companies are making arrangements to use the process. The authorities in Sweden have most fully investigated the whole process, and have pronounced it perfect. The large steel circular saw- plate exhibited was made by Mr. Goranson, of Gefle, in Sweden, the ingot being east direct from the fluid metal, within fifteen minutes of its leaving the blast furnace. In France, the process has been for some time carried on by the old-established firm of James Jackson and Son, at their steel works, near Bordeaux. This firm was about to go extensively into the manufacture of puddled steel, and indeed had already got a puddling furnace erected and in active operation, when their attention was directed to