ps and the flocks now found on the surface of the habitable earth are
the necessary outcome of preceding harvests and preceding flocks and of
all that has been done to maintain and increase them; so, too, if we
look at the universe as a whole, the present condition of that whole is,
if the scientific postulate of invariable sequence be admitted, and in
as far as it is admitted, the necessary outcome of its former condition;
and all the various forms of matter, whether living or inanimate, must
for the same reason and with the same limitation be the necessary
outcome of preceding forms of matter. This is the foundation of the
doctrine of Evolution.

Now stated in this abstract form this doctrine will be, and indeed if
Science be admitted at all must be, accepted by everybody. Even the
Roman Church, which holds that God is perpetually interfering with the
course of nature, either in the interests of religious truth or out of
loving kindness to His creatures, yet will acknowledge that the number
of such interferences almost disappears in comparison of the countless
millions of instances in which there is no reason to believe in any
interference at all. And if we look at the universe as a whole, the
general proposition as stated above is quite unaffected by the
infinitesimal exception which is to be made by a believer in frequent
miracles. But when this proposition is applied in detail it at once
introduces the possibility of an entirely new history of the material
universe. For this universe as we see it is almost entirely made up of
composite and not of simple substances. We have been able to analyse all
the substances that we know into a comparatively small number of simple
elements--some usually solid, some liquid, some gaseous. But these
simple elements are rarely found uncombined with others; most of those
which we meet with in a pure state have been taken out of combination
and reduced to simplicity by human agency. The various metals that we
ordinarily use are mostly found in a state of ore, and we do not
generally obtain them pure except by smelting. The air we breathe,
though not a compound, is a mixture. The water which is essential to our
life is a compound. And, if we pass from inorganic to organic
substances, all vegetables and animals are compound, sustained by
various articles of food which go to make up their frames. Now, how have
these compounds been formed? It is quite possible that some of them, or
all o