204 Mr. Howard's Experiments and Observations 
approach still more nearly to each other, so as absolutely to come 
into contact, and in that manner to form a kind of chain, folded 
upon itself in the interior part of the substance, and leaving a 
great number of cavities between the links of the chain so 
folded. Let us then suppose, that the earthy substance with 
which these cavities are filled, being very porous, and having 
but a small degree of consistence, should (as may happen by a 
variety of causes) be destroyed. It is plain, that if such a 
destruction were to take place, the iron alone would remain; 
and, being thus left bare, it would appear in the form of a mass, 
more or less considerable, of a cellular texture, and as it were 
ramified ; such a form, in short, as that in which most of the 
native irons we are acquainted with have been found. May it 
not be fair to attribute to such an origin, the native iron found 
in Bohemia, a specimen of which was presented by the Academy 
of Freyberg to Baron Born, and which came, with the rest of 
his collection, into the hands of Mr. Greville ? May not such 
also, notwithstanding the enormity of its bulk, be the origin of 
the mass of native iron found in Siberia, near Mount Kemirs, 
by the celebrated Pallas ? 
We have already seen, in the results of the analyses made by 
Mr. Howard, of the various stones above described, that he 
constantly found a certain proportion of nickel mixed with the 
iron they contained. This circumstance recalls to our notice 
the observations that were made by Mr. Proust, some time ago, 
respecting the mixture of nickel in the native iron of South 
America ; and tends to give some additional support to the opi- 
nion hinted at in the foregoing paragraph. 
The circumstances just mentioned, naturally gave to Mr„ 
Howard, as well as to me, a desire to know whether the 
