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19. It lias been suggested by a man of great eminence as a 
physicist, that vegetable life may have been evolved in another 
planet and have been thrown on to our earth when such planet 
broke up, by means of a meteoric stone. I only mention such 
a theory to show how wild may be the speculations of even 
great philosophers on this subject. We have no proof that 
vegetable or animal life exists, or has existed, in any other 
world than our own, and we know that the friction of our 
atmosphere would destroy, by causing intense heat, any such 
organism on meteors. Such a means of introducing life into 
our globe would spoil the potentially-endowment theory, 
and destroy all belief in the interference of a supernatural 
Being in the origin and progress of life on our globe, leaving 
such origin to the chance shot of a broken rock deviated 
from its course round the sun, and falling upon a plantless 
and lifeless world. Such a wild, hopeless, cheerless, unscientific 
theory could do nothing towards an explanation of the origin of 
species, inasmuch as it would'merely relegate to another broken- 
up planet that creation which the science of the 19th century 
dares not face on this. 
20. The earth becoming covered with verdure, the potentiality 
of the original germ, selecting its own spot and its own 
moment, is required by the doctrine of evolution to effect a new 
exercise of forces hitherto dormant for myriads of ages. A 
“ self-adjusting " principle comes into play, and the plant is 
evolved into an aniqial. 
21. Where, when, how, or why, the theory does not explain. 
Exercising his finite mind, man treads fearlessly on the path 
of the Infinite. He has seen an egg become a chicken, a 
pigeon's plumage vary, a bright feather in a bird's tail entranc- 
ing its mate, and upon foundations slight as these he ventures 
to unravel the greatest, the grandest, the most sublime, and 
the most divine of all mysteries — that of Creation. 
22. I remark that without an atmosphere no plant or animal 
could live or grow. Therefore, before the plant or animal there 
must have been an atmosphere, and geology tells us plainly 
enough that such atmosphere has been modified from time 
to time to meet the requirements of living things on the earth. 
Did that occur by chance ? Did that beautiful combination of 
oxygen, nitrogen, and carbonic acid — a compound of the same 
constitution in every part of the earth — come into existence by 
“ natural selection" or the “ struggle for existence"? * 
* A writer in the Edinburgh Journal for Dec., 1872, has discovered that, 
among other good things, the atmosphere of Edinburgh contains more oxygen 
than other places. 
