Pig Iron undergoes during its conversion into Wrought Iron. 173 
the quarter of an hour which has elapsed since the taking of 
No. 4 sample, a large proportion of its carbon, equal to 20 per 
cent. of its weight, whilst the silicium, on the contrary, has 
remained nearly stationary. 
First analysis. Second analysis. Mean. 
Carbon. . . . 1614 1681 1647 
Silicium. . . . 0188 0178 0°185 
6th Sample, taken out at 1» 40™ p.m. 
The reason why this sample was taken only five minutes after 
the last sample, was, that the mass in the furnace was rapidly 
transforming itself into two distinct products, viz. the scoria on 
the one hand, and small globules of malleable iron on the other. 
We attached some importance to this sample, as the workman 
was on the point of beginning the balling or agglomerating the 
globules of iron, so as to form large balls of about 80 lbs. weight, 
to be hammered and rolled out into bars. Whilst the mass 
taken out for analysis was cooling, small blue flames of oxide of 
carbon issued from it. These were similar to those observed in 
Nos. 4 and 5, but were not so abundant. The appearance of 
this sample was very similar to the last one, with the exception 
that the scoria was not so intimately mixed with the globules of 
iron, and that these were larger, and slightly welded together 
when hammered. The piper rtions of carbon and silicium were 
as follows :— 
First analysis. Second analysis. Mean. 
Carbon.) .f s:ite:ces» 4258 1160 1:206 
Silicium, . . . 0167 0-160 0163 
When these figures are compared with those of the previous 
analysis, it is interesting to observe, that whilst the silicium re- 
mains’ nearly stationary, the carbon rapidly diminishes; for im 
the five minutes which elapsed between the taking out of the 
two samples, there was 28 per cent. of the carbon burnt out. 
This rapid decrease of carbon in the iron is maintained during 
the remaining ten minutes of puddling. In fact, in one quarter 
of an hour, viz. from 1 35™ to 14 50™, the iron lost 50 per cent. 
of the carbon which it contained at 1) 35™, 
7th Sample, taken out at 1» 45™. 
This sample was obtained when the puddler had began to 
ball. The appearance of the sample, although similar to the 
last, differs from it by the granules being rather larger, and 
nearly separated from the scoria, which forms a layer at the top 
and bottom of the mass. These granules are also much more 
malleable, for they are easily flattened under the hammer, This 
