128 THE HISTORY OF CREATION. 
broken crust. Lyell, on the other hand, showed that we cam 
explain the formation of such enormous chains of mountains. 
quite naturally by the same slow and imperceptible risings and 
depressions of the earth’s surface which are still continually 
taking place, and the causes of which are by no means 
miraculous. Although these depressions and risings may 
perhaps amount only to a few inches, or at most a few feet, 
in the course of a century; still, in the course of some 
millions of years they are perfectly sufficient to raise up the 
highest chains of mountains, without the aid of mysterious 
and incomprehensible revolutions. In like manner, the 
meteorological action of the atmosphere, the influence of rain 
and snow, and, lastly, the breakers on the coasts, which by 
themselves seem to produce an insignificant effect, must cause 
the greatest changes if we only allow sufficiently long 
periods for their action. The multiplication of the smallest 
causes produces the greatest effects. Drops of water produce 
a cavity in a rock. 
I shall afterwards be obliged again to recur to the im- 
measurable length of geological periods which are necessary 
for this purpose, for, as we shall see, Darwin’s theory, as 
well as that of Lyell, renders the assumption of immense 
periods absolutely necessary. Ifthe earth and its organisms 
have actually developed in a natural way, this slow and 
gradual development must certainly have taken a length of 
time which surpasses our powers of comprehension. But as 
many men see in this very circumstance one of the principal 
difficulties in the way of those theories of development, I beg 
leave here to remark that we have not a single rational 
ground for conceiving the time requisite to be limited in any 
way. Not only many ordinary persons, but even eminent 
