DISSERTATION ON THE ATMOSPHERE. 259 
great heat the history of Garnet bears testimony. This 
mineral occurs in gneiss, and its consideration would seem 
to remove every doubt as to its having experienced a tempe- 
rature sufficient to fuse it where it lies, though the heat was 
incapable of liquifying the surrounding rock. 
Due to the action of the same agent, the earthy carbonates 
seem to have suffered a similar change, the fused mass being 
suppos.ed by condensation to have given rise to the varie- 
gated and useful marble. 
Unfortunately for this hypothesis of fusion and subse- 
quent crystallisation, long before the temperature required 
could be attained the power of affinity would have been 
overcome. This is shown in the reduction of carbonate of 
lime by ignition when the air receives carbonic acid and lime 
only remains. 
This would happen in any other atmosphere than one of 
pure carbonic acid. How, then, can we reconcile this fact 
on the one hand, with the opinion that physical agencies in 
every age have produced “ equal effects in equal times, 5 ’ and 
on the other side with the above results of exact experi- 
ment. No such difficulty appears to have occurred to other 
writers, but I must confess my inability to explain rationally 
the formation of marble from accepted views of the condi- 
tion of the primeval atmosphere, except by referring the 
formation of such crystals to electro-chemical power, which 
is indeed the most likely. Heat is therefore no true cause, 
taking the meaning Newton attached to this expression. 
That is, it is not referable to, but indeed contrary to, the 
known action of forces. That heat is an adequate cause, or 
that the existence of such crystalline masses necessitates the 
adoption of the fusion hypothesis rests on very debateable 
evidence. 
Nevertheless, in speculating upon the forces which have 
affected and still react on matter, there is much, I think, 
which requires the cognisance of faith. A bent spring loses 
its elasticity, and why ? Owing to molecular change is the 
reply. What is implied in such a transformation ? Much 
every way. The same language is employed to explain the 
passage of white crystalline and translucent phosphorus, 
readily inflammable, into amorphous phosphorus, which is 
reddish-brown, and scarcely inflammable. Again, how great 
the contrast betwixt common charcoal, which is per- 
fectly amorphous and black, with the diamond, in its trans • 
parent octohedral crystals ! Chemically the same, but ex- 
trinsically, how different they seem. The extraordinary rela- 
tions to space certain bodies have been shown to possess by 
