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the experiments were undertaken for the purpose of ascertain- 
ing how far, and to what extent, an admixture of nickel would 
improve other metals ; with the view, among other objects, to 
obtain increased tenacity in the metals employed in the cast- 
ing of mortars and heavy ordnance. 
During the last two years innumerable tests and experiments 
have been made for this purpose with more or less success ; 
but the ultimate result appeared to be, in the opinion of 
the author and others, that for the casting, or rather the 
construction, of heavy artillery, there is no metal so well cal- 
culated to resist the explosion of gunpowder as a perfectly 
homogeneous mass of the best and purest cast iron when 
freed from sulphur and phosphorus. 
In the discussion which followed the reading of the paper, 
Mr. Calvert said that it was highly probable that nickel 
caused the increased brittleness of cast iron, just as carbon, 
phosphorus, and sulphur, — but that the result with malleable 
iron might probably be very different ; and, as meteoric iron 
is malleable, the trial could only be complete when soft iron 
and nickel were united ; nevertheless, these experiments, as 
far as cast iron is concerned, were decidedly new and of 
great value. 
It was further suggested, that considering the peculiar 
proportions of meteoric iron, it was desirable to extend the 
experiments, and that Mr. Calvert be requested to render 
his assistance to the President for that purpose. 
