1864. | Metallurgy. 531 
inquiry into this important division of Iron manufacture, and of 
the zeal with which author and engraver have laboured to produce the 
most satisfactory results. With the enormous development of our 
Iron industries, there has been, naturally, greatly increased attention 
to all the details of manufacture. Every stage of the process, from 
the casting of “mine” (iron ore) into the furnace, to the flowing out 
of pig-iron, has been rigorously investigated by the author; and, again, 
every step in the progress of manufacture, into “merchant bars,” or 
the conversion of iron into steel, has been subjected to the most 
minute examination. The attention which has been given by Dr. 
Percy to all these points has ensured a great degree of exactness in 
his descriptions, and there is little left to be desired in any one of 
them. 
The invention of “ Puddling” by Henry Cort is now very satis- 
factorily éstablished ; and the story of his ruin, through the fraudulent 
conduct of his partner, Mr. Samuel Jellicoe, and the stupidity and 
blundering of the government officials with whom he had to deal, is 
stated by Dr. Percy with great lucidity, and with the most honourable 
and kindly feeling. We should perhaps explain, for the benefit of 
some of our readers, that “puddling” is a name given to a process by 
which pig-iron, molten on the bed of areverberatory furnace heated by 
flame, is converted into malleable tron through the decarbonizing action 
of the oxygen of the air circulating through such a furnace. Pig-iron 
is, essentially, a compound of Carbon and Iron: other matters are 
combined with, and influence its quality, such as Sulphur, Silicon, 
Manganese, and Phosphorus. These are removed either by combina- 
tion with oxygen when they escape in the gaseous form, or by mixing 
with the slag, when they are mechanically removed. The mean of 
many analyses of Pig-iron gives about 3 per cent. of Carbon, 23 per 
cent. of Silicon, and 94 of Iron; that of Malleable Iron beg about + 
of a percentage of Carbon, and } of Silicon. This is to be considered 
as a general statement of the character of these two varieties of iron, 
the difference it will be seen depending upon the absence of Carbon 
or Silicon. Many processes have been devised to supersede the 
laborious operations of puddling, but none of them have been as yet 
entirely successful. 
Steel is a third condition of Iron, in which some Carbon exists in 
a peculiar state of chemical combination with the Iron. Dr. Percy 
says :— 
“The production of Cast-iron into Steel by partial decarburization may 
be effected in several ways: and of these are three of chief importance, 
namely, fining in a hearth with charcoal as the fuel, puddling in the rever- 
beratory furnace, and the Bessemer process. The first is the ancient 
method, which is still extensively practised ov the Continent, especially in 
Styria; the second is only of recent date, but has, nevertheless, made 
rapid progress ; and the third is the most novel, and certainly destined to 
play an importaut part in the world. If Steel be regarded simply as Iron 
carburized in degrees intermediate between Malleable and Cast-iron, then 
it is obvious that the latter, during its conversion into the former in the 
process of fining and puddling, must pass through the state of Steel. 
Accordingly, it is found that by suitably regulating and arresting the 
