MECUANICS AND USEB^UL ARTS. 25 



geal or come to nature, it still contains about 2 per cent, too 

 niucli carbon. By transferring and exposing it, for 3 or 4 

 hours, in the reverberatory furnace in a liquid state, to a neutral or 

 slightly oxidizing flame under a cover of oxidizing cinder, this 

 excess of carbon gradually works off; and when it is worked 

 down to the point desired (which may be asceitained by testing 

 samples), it is tapped into ingots. To temper and improve the 

 steel or homogeneous iron, in most cases, before tapping the metal, 

 a small proportion of manganese in some of its combinations is 

 added. 



It has been found beneficial to let the metal decarbonize to an 

 extent slightly below the desired degree of carbonization of tlie 

 steel or homogeneous iron, and then to improve and recarbonize 

 the metal by adding a small proportion of spiegel iron, amount- 

 ing to about 1 per cent, of the whole. The carbon may, in some 

 cases, be partly reduced by the addition of wrought iron, or, it 

 may be, other malleable iron, in any form containing less carbon 

 than the desired steel. In practice, it has been found advanta- 

 geous for this purpose to make use of scrap bars, blooms, or balls 

 in a heated state, which are gradually introduced and melted with 

 the fluid metal tapped from the puddling furnace. 



In some cases, cast steel or homogeneous iron is made by using 

 ordinary puddle balls in combination with the fluid metal tapped 

 from the puddling furnace, for which purpose it is found con- 

 venient to partially tap or transfer the contents of the puddling 

 furnace just before the metal comes to nature, and to allow one 

 half, less or more, of its contents to run into the reverberatorv 

 melting furnace. The rest may be allowed to continue working 

 in the puddling furnace until it has thoroughly come to nature, 

 and has become malleable, and the cinder has dropped, when it 

 may be transferred either by shovels or in lumps and adeled to the 

 fluid metal previously tapped from the puddling furnace on to 

 the hearth of the reverberatory melting furnace. 



The whole of the metal thus mixed, after being thoroughly 

 fluidified and brought to the desired point of carbonization in the 

 reverberatory steel-melting furnace, may then be run into ingots. 

 Or four or more puddling furnaces may be employed to one melt- 

 ing furnace, and the entire contents of one or several of the pud- 

 dling furnaces may be transferred before the period of coming to 

 nature, while yet fluid, and tlie contents of the remaining furnaces 

 may be transferred after the contents have got into nature ; the 

 entire contents of the whole of the puddling furnaces may then 

 be melted together in the steel-melting furnace. Or the crude 

 steel metal, tapped from the puddling furnace at the period 

 named, may, particularly when it is desired to treat it in crucibles, 

 be run into moulds as flat cakes, which, being broken in pieces, 

 may be remelted in crucibles (or in the reverberatory furnace), 

 in conjunction with malleable iron or with iron ore, to form steel. 

 — Mechanics' Magazine, Aug., 1868. 

 3 



