Cast Iron, Steel, and Malleable Iron. 585 



cemented steel has obtained the name of blistered steel, and 

 the oxygen of the part of this gas which is in contact with 

 the sides of the blister occasions those fine tints of yellow and 

 blue with which the inside of the blisters is generally covered. 



It is generally asserted that the outside of the cemented 

 bar of steel contains more carbon than the inside, and that 

 therefore the fusion of the cemented bar served to spread the 

 carbon more equally throughout the mass. This is contrary 

 to fact. When the iron bar which is to be cemented is of a 

 suitable thickness, the process of carbonization commences, 

 like the process of the reduction of iron ores, almost simul- 

 taneously at the centre and at the outside of the bar ; and I 

 have often found that the inside of the cemented bar contained 

 a greater quantity of carbon than the outside. The quantity 

 of carbon imbibed by each portion of the bar depends en- 

 tirely on the quantity of carbon first contained in the differ- 

 ent parts of the iron bar, as well as on the carburet of silicon 

 contained in it; and this different degree of carbonization may 

 even be detected by the eye, from the various forms of cry- 

 stallization contained in the bar. 



This, as well as other chemical phaenomena which have 

 not received sufficient attention, may be explained by the 

 law which causes one atom of water in the voltaic circuit to 

 evolve hydrogen and oxygen at the same moment at two di- 

 stant points. 



In conclusion, I annex an analysis of the best English cast 

 steel, to controvert the modern assertion that the best cast- 

 steel bars consist only of a pure compound of carbon and 

 iron. The analysed specimen was a fragment of an excellent 

 razor, forged in my presence, in the workshop of Mr. 

 Rodgers, of Sheffield, of the specific gravity of 7*92. 



Silicon. . . . 0-52043 



Aluminum . . O'OOOOO 



Manganese . . 1-92000 



Arsenic . . . O'OSiOO 



Antimony. . . 0-12100 



Tin Traces. 



Phosphorus . . 0-00000 



Sulphur . . . 1-00200 



Azote .... 0-18310 



Carbon . . . 1-42800 



Iron .... 93-79765 



Loss .... 0-09382 



100-00000 

 PJiil Mag, S. 3, Vol. 16. No. 106. Stippl. July 1840. 9. 11 



