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Alluding to the presence of diamonds in meteorites, Mr. 
Pankhurst said he had mentioned carbon as one of the constituents 
of these sky-stones. ‘The commonest substance on the crust of 
the earth, carbon, is one of the rarest in its crystalline form, namely, 
as the diamond. ‘The scientific world was somewhat startled a few 
years ago by the announcement that diamonds had been found in 
meteorites. The carbon in this case in not transparent, but black, 
opaque, and exceedingly hard. Within the last two or three years, 
some extraordinary stones have fallen which have yielded this 
crystallised carbon. ‘The rock with which it has been associated 
is that silicate of magnesia and iron to which I have before alluded. 
One common form of it is Olivine. And hereby hangs a tale and 
a very extraordinary one. Here, he said, pointing to a specimen 
on the table, is a diamond, in its rocky matrix from South Africa. 
The diamond-bearing rocks of that part of the world are all of this 
character. It is an old lava probably erupted from great depths. 
In the course of ages it has been much altered by the infiltration 
of water, &c. ; but here and there particles are found of the original 
rock, and this is strictly analogous in composition to that silicate 
of magnesia and iron which is the faithful companion of all 
meteorites, and which forms so large a constituent of the rocky 
matter in which the last sky-diamonds have been found. Yet 
another fact not less extraordinary. A diamond is nearly related 
to petroleum. A diamond is pure carbon. Petroleum is carbon 
plus hydrogen. ‘The origin of such large quantities of this sub- 
stance in the lower strata of the earth’s crust has long been one of 
the great unsolved problems of geology. Now, strange to say, 
there are meteorites from which a hydro-carbon allied to petroleum 
has been extracted. Some five or six meteorites are known which 
are more or less bituminous. 
Whatever origin we may ascribe to meteorites, there is little 
doubt but that they represent to us the constitution of the earth 
in the earlier ages of its existence. They are representatives of a 
time when its carbon, hydrogen, sulphur, iron, &c., formed com- 
binations or assumed shapes not possible under later conditions. 
What, then, is the origin of those singular visitors to our globe? 
Have they been ejected from the volcanoes of the earth in the 
earlier epochs of its history, circulating for ages round the sun 
until the attraction of the parent has brought them back again to 
it? There is much to be said both for and against such a theory. 
The density of the earth as a whole is greater than that of the 
rocks on its surface. ‘The interior is, therefore, possibly to some 
extent metallic. The earth is alsoa great magnet. If iron pre- 
dominates in the earth’s interior, as in meteorites, a remarkable 
phenomena would be explained. Are they, again, the shattered 
fragments of a planet that has fulfilled its destiny, the dust and 
ashes of a vanished world? This is an idea that has found favour 
