402 Proceedings of the Royal Physical Society. 
manifest ; a little of the metal was then filed off, and put into 
the hands of Dr Murray Thomson, lecturer on Chemistry, with- 
out letting himknow its history, and he informed me the filings 
consisted of iron, with a proportion of nickel. Native iron of 
terrestrial origin heing almost chemically pure, and never con- 
taining any proportion of nickel, the mass of iron was therefore 
of meteoric origin, being an alloy of iron and nickel ; the latter 
generally existing in very small proportion to the former. 
The peculiar shape and appearance of this mass of metal 
itself, so entirely unlike any handiwork of man, was indeed 
almost proof enough to many of its meteoric character, of 
whichj however, there was now no room for doubt. 
The subsequent steps taken to learn the special peculiari- 
ties of its structure and chemical analysis have now to be 
detailed. 
Section of Meteoric Iron. — The iron was cut longitudi- 
nally into two portions, by Mr Young, lapidary, as I was 
anxious to see whether any difference of structure existed in 
any part of the mass, or whether cavities containing olivine 
could be detected. Nothing of this kind, however, was dis- 
closed, the mass being equally solid, dense, and steel-like in 
its appearance throughout, and the colour beautifully bright 
and white, like steel. With Mr Alexander Bryson's assist- 
ance, and a new steel file, I next proceeded to rub down as 
much of the surface of one of the pieces, as would suffice for a 
minutely detailed chemical analysis being made ; and in 
assisting to do so, soon made a practical discovery of the 
extreme hardness or toughness of the metal, which in a com- 
paratively short time turned the sharp points on the file itself. 
The hands soon became much blackened by the operation, as 
if plumbago was mixed with the iron. There seemed no doubt 
the metal was steel, from the carbon which was so manifestly 
present. The surface of the mass varied somewhat in its re- 
sistance to the file ; its prism-like point was very close and 
hard externally, and contained apparently more of the black- 
ening part of the iron ; the upper and rounded portions were 
also hard and dense, at least externally, offering more re- 
sistance to the file ; and the tool seemed to have less effect 
upon the iron when it was used across the mass, than in 
