CHEMICAL SCIENCE. 219 



First analysis. Second analysis. Mean. 



Carbon, 2-335 2-276 2.305 



Silicium, 0-187 0-178 0-182 



Fifth Sample, taken out at Ih. 35m. p. M. 



This sample is a most important one in the series, as it is the first in which 

 the iron is malleable, and flattens when hammered. It was ladled out of the 

 furnace just as the boil was completed, and the swollen mass began to sub- 

 side. The damper at the top of the chimney was drawn up, so that a very 

 rapid draft was established through the furnace. The puddler also changed 

 his tool, leaving the rubble, and taking the puddle to work with. When cold, 

 it partakes of the appearance of Nos. 3 and 4 samples, the mass being 

 spongy and brittle, as in No. 4, but less granulated, and like No. 3, being in 

 separate globules, mixed with the scoria. The granules are black externally, 

 but are bright and metallic when flattened. The analysis of these globules 

 proves that the mass of iron in the furnace has lost during 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, while the silicium, on the 

 contrary, has remained nearly stationary. 



First Analysis. Second Analysis. Mean. 



Carbon, 1-614 1-681 1-647 



Silicium, 0188 0-178 0-185 



Sixth Sample, taken out at Ih 40m p. M. 



The reason why this sample was taken out 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 glob- 

 ules 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 agglo- 

 merating the globules of iron, so as to form large balls, of about eighty 

 pounds 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 proportions of carbon and silicium were as 

 follows : 



First Analysis. Second Analysis. Mean. 



Carbon, 1-253 1160 1-206 



Silicium, 0-167 0-160 0-163 



When these figures are compared with those of the previous analysis, it is 

 interesting to observe, that whilst the silicium remains nearly stationary, the 

 carbon rapidly diminishes ; for in the five minutes which elapsed between 

 the taking out of the two samples, there was twenty-eight 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 Ih 35m to Ih 50m., the iron lost fifty per cent, of the carbon 

 which it contained at Ih 35m. 



Seventh Sample, taken out at Ih 45m p. M. 

 This sample was obtained when the puddler had begun to ball. The, 



