15 
geologists, to the men of the hammer, who have been described as 
collectors of petrified shells and bones. G+ ology, I know, is not 
a very popular study, and thereby men miss a source of very great 
pleasure. Let me just say in passing that though so generally 
looked upon as dry and uninteresting, it is nevertheless a science 
more replete with wonderment, more abounding in mysterious 
puzzles and problems, fuller of fairy tales, giant deeds, and mar- 
yellous transformations, than any other subject known to the 
student of nature. And yet so few take it up. To me I confess 
it has long been a marvel that here in Folkestone, a district so rich 
in geological material, that men and women come yearly from all 
parts to enrich their geological knowledge, the local students could 
be numbered more than once on the fingers of one hand. Our 
museum will show you that we are frequently coming across the 
skeletons of mammoth, rhinoceros, hippopotamus, and other 
creatures, which must have died on the spot where we find them 
possibly 50,000 or 60,000 years ago. Yet though we have 
five or six times started winter classes in geology, on orly one 
occasion did the number of students amount to six. This is a 
digression. Now to our task—How was this ice age discovered ? 
One great lesson learned by the geologist, and indeed by every 
naturalist, is the prevalence of orderly arrangement in nature—the 
reign of law. Thevery mat rials composing the crust of the earth, 
as far down as we can possibly obtain any knowledge of them 
whatever, instead of being (as they seem to be) scattered at ran- 
dom, are arranged each one in a certain position, relative to the 
rest, all according to one definite plan. There are two great 
divisions of these rocks, viz.: (a) Those formed by the agency of 
heat, ¢.v,, lava, basalt, granite, &c., known as Igneous rocks; 
(b) those which, like limestones and sandstones, were formed in 
water (these are called Aqueous rocks). Leaving the former out of 
sight for our present purpose, we find that the rocks formed in 
water are more or less perfectly stratified, ¢.c., arranged in layers 
one above the other, as we may see in the lower Road. Our 
diagram illustrates this. Here is chalk, oolite, carboniferous, old 
red sandstone, &c. No one of these, in whatever part of the world 
it may be found, ever occurs out of its proper place. Nowhere can 
you find oolite or lias above the chalk; no greensand or London 
clay ever occurs below the coal rocks, &&. Hence we can classify 
them all according to their relative ages, those at the bottom being 
of course the oldest. Moreover, each particular set of beds or strata 
contains within it the plants and animals which flourished in 
that neighbourhood while those beds were being formed ; and the 
set of remains differs in each group of strata, so that it is possible 
to extract the history of the earth from these rocks and in many 
