24 MINERALOGY AND LITHOLOGY. 
which have fallen from above, has been often affirmed and often doubted. 
The subject has, however, received new interest from its proved presence 
in basaltic rocks, and from the discussion in regard to the origin of the 
numerous immense masses of iron which have been found in Greenland. 
My attention was called to this subject by observing a bright particle 
which was embedded in the midst of a grain of magnetite in a thin sec- 
tion of the chrysolitic gabbro from Mt. Washington. This particle pos- 
sessed a lustre so resembling metallic iron, that I tested it with a solution 
of sulphate of copper, and found that, like metallic iron, it became cov- 
ered with a film of copper, which proved it to be iron. On testing nu- 
merous other specimens, I was but twice able to repeat the observation ; 
hence, though no very great weight can be attached to the experiment, 
it may be said to exist in these rocks, and, if the undecomposed trap 
rocks from Waterville, or from the Mt. Washington river, are pulverized, 
the magnetic constituents withdrawn by a magnet, and these constituents 
treated with a solution of sulphate of copper, on examining with the 
microscope, occasionally one will see bits of reduced copper, which is 
evidence of the presence of metallic iron. The efficacy of this reaction 
has been doubted ; but my observation of grains of iron, though minute, 
is sufficient to call the attention of those who may study these rocks in 
the future to the possibility of finding it in more abundance, and under 
such circumstances that conclusions can be safely drawn from its occur- 
rence. 
No meteoric iron has, so far as I know, been found in this state. I 
might mention that a supposed meteorite, which was found in Concord, 
has been considered important from the circumstance that it contained 
no iron, this absence rendering it unique among meteorites. This stone 
was described by Prof. B. Silliman, Jr., in 1847,* and was shown to con- 
sist of tersilicate of magnesia and silicate of soda; but although the cir- 
cumstances of its fall seem to be well authenticated, it is but fair to state 
that in the cabinet of Yale college, where the specimen is preserved, it is 
put among the doubtful specimens. The reason of this doubt is, that its 
very peculiar composition, and its slaggy, artificial look, are thought to 
weigh seriously against its celestial origin. 
* Am. Four. Science, ii, vol. 4, p. 353- 
