^54 
Mr Stodart and Mr Farmiay 
trifling addition of price cannot operate against its very general 
introduction. The silver alloy may be advantageously used for 
almost every purpose for which good steel is required. 
Our next experiment made in the large way, was with steel 
axid platina. 10 lb. of the same steel, with ji^tli part of pla- 
tina, the latter in the state produced by heating the ammonia 
muriate in a crucible to redness, was forwarded to our agent, 
with instructions to treat this in the same way as the last named 
metals. The whole of this was returned in bats remarkable for 
smoothness of surface and beauty of fracture. Our own obser- 
vation, as well as that of the wwkmen employed to make from 
it various articles of cutlery, was, that this alloy, though not 
so hard as the former, had considerably more toughness : 
this property will render it valuable for every purpose where 
tenacity, as well as hardness, is required ; neither will the ex- 
pence of platina exclude it from a pretty general application in 
the arts ; its excellence will much more than repay the extra 
cost. 
The alloys of steel with rhodium have also been made in the 
large way, and are perhaps the most valuable of all ; but these, 
however desirable, can never, owing to the scarcity of the metal, 
be brought into very general use. The compound of steel, iri- 
dium and osmium, made in the large way, is also of great value ; 
but the same cause, namely, the scarcity and difficulty of pro- 
curing the metals, will operate against its very general introduc- 
tion. A sufficient quantity of these metals may perhaps be ob- 
tained to combine with steel for the purpose of making some 
delicate instruments, and also as an article of luxury, when 
manufactured into razors. In the mean time we have been en- 
abled, repeatedly to make all these alloys (that with palladium 
excepted) in masses of from 81b. to ^Olb. each ; with such libera- 
lity were we furnished with the metals from the source already 
named. 
A point of great importance in experiments of this kind was, 
to ascertain whether the products obtained were exactly such as 
we wished to produce. For this purpose, a part of each pro- 
duct was analysed, and in some cases the quantity ascertained ; 
but it was not considered necessary in every case to verify the 
quantity by analysis, because, in all the experiments made in 
