1824.] M. Brcant on Damasked Sleet. 269 



to metallic alloys which were owing more particularly to an 

 increased proportion of carbon. 



" I am very far from disputing the existence of metallic alloys 

 in the oriental sabres, although, in the few fragments which I 

 have had an opportunity of examining, I have not found either 

 silver, gold, palladium, or rhodium ; I think it very probable, 

 however, that different combinations may have been attempted. 

 A people who knew how to harden copper by alloying it with 

 other metals, are very likely, from analogy, to have tried the 

 same process with iron. 



" This view of the subject led me to form various metallic 

 alloys, some of which gave satisfactory results. One of the 

 sword blades which I presented to the Exhibition contains one- 

 half per cent, of platina, and a larger proportion of carbon than 

 common steel ; its dam. sk is owing particularly to the latter. 

 Excellent razors have been made with this alloy. 



" At all events these alloys should not be tried till we have 

 fully ascertained the effects of pure carbon, and we ought to 

 begin by combinations in very small proportions. The addition 

 of a metal makes the steel more brittle ; however, I have 

 obtained ductile alloys, in raising the quantity of gold and 

 platina, as high as 4 per cent, and that of copper and zinc 

 to 2. 



" As to zinc, certain precautions are necessary in forming 

 alloys with that metal ; it occasions violent detonations, where- 

 fore it must be added to the fused metals in very small portions 

 at a time. In forging steel alloyed with zinc, part of the metal 

 is volatilized and dissipated. 



" Manganese unites readily with steel, and the alloy forges 

 easily ; but it is very brittle when cold : I have made gravers 

 with this alloy which cut iron without having been tempered : 

 the damask of this mixture is very black and well defined. 



" Plumbago appeared in some instances to soften steel which 

 had been rendered too brittle by an excess of carbon ; at least I 

 have obtained excellent results with 100 parts of steel, 1 of 

 lamp-black, and 1 of plumbago. 



" But a very remarkable experiment, from the advantage that 

 may result from it in working on a large scale, is one which 

 showed that 100 parts of si.ft iron and 2 of lamp-black fuse as 

 readily as common steel. Probably the whole of the carbon 

 does not combine. Some of our best blades are produced from 

 this combination. It has the disadvantage of contracting very 

 much on cooling, and the buttons generally have cavities which 

 make them very difficult to forge ; but if, instead of damasked, 

 we only want to make common steel, the contraction on cooling 

 may be prevented by casting this compound in an ingot mould. 



" This experiment teaches us that the previous cementation 

 '■! the iron is not necessary in order to obtain very good steel. 



