on some ancient metallic Arms and Utensils. 419 
course was very different in its external appearance from the 
allays of copper by tin. Like the allay of Experiments 1st 
and 13th, it was too soft, and, as the artists term it, clingy, to 
receive the impression of lines, figures, and letters, or for in- 
struments in which holes are to be drilled. 
The solution of this allay in nitric acid was blue, like those 
of the preceding allays and old metals, but there was no white 
deposit. 
Observation. This is the proper place for me to observe, 
that all the above allays, and the gun metal, melted at a lower 
temperature than copper does ; and, as far as I could deter- 
mine, the temperature of fusion decreases as the proportion of 
tin increases. 
The next experiments were made not only to satisfy myself, 
that if iron had been an ingredient in the ancient metals, it 
must have been made appear by the test employed ; but also to 
determine the question made by some chemists, whether cop- 
per can be allayed by iron ; and to show, as others have as- 
serted, the allays of copper by iron, which were employed by 
the ancients. 
From the writings of many able chemists I was inclined to 
suppose, that a malleable uniform metal could not be com- 
posed of copper and iron, without the aid of an intermede. I 
therefore, in the first place, used tin as the intermede. 
Perhaps some of these experiments next to be related may 
not be found immediately relative, but as they occurred in the 
course of investigation, and as I believe few experiments of 
the same kind have been published, perhaps they will be found 
useful. 
Experiment 13. 2000 grains of tin were melted with 1000 
