millions to the previous sum. The symbolic "_ad infinitum_" could be
made as adequately representative in the case of an infinite series of
men or animals in unlimited time, as of an infinite series of feet or
inches in unlimited space, or of an infinite series of hours or minutes
in the past eternity. And as for Bentley, on the other hand, he ought
surely to have known that all infinities are not equal, seeing that
Newton had expressly told him so in the second of his four famous
letters; but that, on the contrary, one infinity may be not only ten
times greater than another infinity, but even infinitely greater than
another infinity; and that so the conception of an infinity of men
possessed of ten infinities of fingers and toes is in no respect an
absurdity. Of the three infinities possible in space, the second is
infinitely greater than the first, and the third infinitely greater than
the second. A line infinitely produced is capable of being divided
into--that is, consists of--an infinity of given parts; a plane
infinitely extended is capable of being divided into an infinity of
infinitely divisible lines; and a cube, that is, a solid, infinitely
expanded, is capable of being divided into an infinity of infinitely
divisible planes. In fine, metaphysic theology furnishes no argument
against the infinite series of the atheist. But geology does. Every
plant and animal that now lives upon earth began to be during the great
Tertiary period, and had no place among the plants and animals of the
great Secondary division. We can trace several of our existing
quadrupeds, such as the badger, the hare, the fox, the red deer, and the
wild cat, up till the earlier times of the Pleistocene; and not a few of
our existing shells, such as the great pecten, the edible oyster, the
whelk, and the Pelican's-foot shell, up till the greatly earlier times
of the Coraline Crag. But at certain definite lines in the deposits of
the past, representative of certain points in the course of time, the
existing mammals and molluscs cease to appear, and we find their places
occupied by other mammals and molluscs. Even such of our British shells
as seem to have enjoyed as species the longest term of life cannot be
traced beyond the times of the Pliocene deposits. We detect their
remains in a perfect state of keeping in almost every shell-bearing bed,
till we reach the Red and Coraline Crags, where we find them for the
last time; and, on passing into o