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the earth was at one time an immense volume of white-hot vapour, which by 
loss of heat and subsequent condensation, was resolved into a globular mass 
of white-hot fluid, that slowly cooled down, and after an enormous lapse of 
time became the solid compact sphere upon which we live. Much of the 
argument m favour of this nebular hypothesis has been drawn from the fact 
that the substance called “ granite,” and which forms a great part of the 
crust oi the earth, bears upon it distinct evidences of igneous fusion at some 
previous period of its existence. Admitting, then, the fact that much of the 
granite of the earth was once in a perfect state of fusion,— I ask, does the 
solidified granite of the present day afford, as it ought to do, undeniable 
proofs that it has cooled down and become solid in the extremely slow and 
gradual manner implied in the nebular theory ? Now, I have examined a 
great number of specimens of granite from various parts of the world, and so 
far from supporting the nebular theory, they all tend to show the extreme 
inaccuracy of that theory. Such, at least, is my opinion ; but upon this 
point 1 leave every one to form an opinion for himself, merely remarking 
that the experiments and results I am now about to relate may be, and I 
hope will be, repeated and verified or contradicted by many other inquirers 
after truth. I have said that granite ought to afford undeniable proofs of the 
rate at which it has cooled down and become solid from the fused condition 
and 1 will here explain in what those proofs consist. Granite is made up of 
an aggregation of three or four different substances, which merely cohere 
together, and have been designated by mineralogists as felspar, quartz, mica, 
and norn blende. But if these substances were once in fusion, and then con- 
stituted one uniform fluid, it is clear that in cooling they must have obeyed 
the. existing laws of chemical affinity, and have arranged themselves into 
their present relative positions before the period of actual solidification. That 
they did obey the ordinary laws of chemical affinity has been proved by their 
analysis, which shows that they have been formed in accordance with the 
rules of atomic proportion ; and that the law of gravitation was then in force 
will not be denied by the nebular theorists, since it is upon this law that their 
whole theory rests. If, then, the substances constituting granite, that is to 
say , the felspar, quartz, mica, and hornblende, segregated themselves durino- 
tlie period of fusion, and were at the same time subject to the law of gravita° 
ion, it is beyond doubt that they would arrange their respective positions as 
regards each other m the exact order of their gravitation, or, as it is called, in 
accordance with the attraction of gravitation, just as we see a piece of lead 
sink m water, and oil swim upon its surface. That the said process of solidifi- 
cation was not rapid but extremely slow requires no illustration, for this con- 
stitutes a part of the nebular theory ; consequently, there was abundant time 
to meet the requirements of gravitation. But it may be urged that perhaps 
the gravitating power of all these substances maybe alike and uniform, con- 
sequently , there might be no disposition for any one of them to sink under or 
to swim upon the others, and therefore, if felspar, quartz, mica, and horn- 
blende possess exactly the same specific gravity, a melted mixture of them 
d r n mt °i USt su< * a arranged granular mass 
as is exhibited to us by an ordinary piece of granite. Here, then, was a 
practical question : are the components of granite all alike in specific weight, 
or are they different ? It is now more than two years ago since I set myself 
down to investigate this matter, and during that time I have examined 
granite obtained from almost every quarter of the globe-from Siberia, 
b p a H- ny ’ 1 Scotla ' ld ’ Inland, Cornwall, the Mont Cenis Tunnel, Upper 
/^l 1 nd P ima M fountains, the Cape of Good Hope, Australia, New 
Zealand, Patagonia, California, and Nova Scotia. As a result of this labour 
I am enabled to say most authoritatively, that not only do the components in 
question differ in their specific gravities, but that this difference is sufficiently 
