taining an immense sandstone block, eight feet six inches in length, with a width of two feet eight inches, and a thickness of three feet four inches.

Discussing the subject, Mr. Lubbock says:

"We must feel that a body of water, with power to move such masses as these, must have been very different from any floods now occurring in those valleys, and might well deserve the name of a cataclysm. . . . But a flood which could bring down so great a mass would certainly have swept away the comparatively light and movable gravel below. We can not, therefore, account for the phenomena by aqueous action, because a flood which would deposit the sandstone blocks would remove the underlying gravel, and a flood which would deposit the gravel would not remove the blocks. The Deus ex machina has not only been called in most unnecessarily, but when examined turns out to be but an idol, after all.”

Sir John thinks that floating ice might have dropped these blocks; but then, on the other hand, M. C. d'Orbigny observes that all the fossils found in these beds belong to fresh-water or land animals. The sea has had nothing to do with them. And D'Orbigny thinks the Drift came from cataclysms.

M. Boucher de Perthes, the first and most exhaustive investigator of these deposits, has always been of opinion that the drift-gravels of France were deposited by violent cataclysms.*

This view seems to be confirmed by the fact that the gravel-beds in which these remains of man and extinct animals are found lie at an elevation of from eighty to two hundred feet above the present water-levels of the valleys. Sir John Lubbock says:

"Our second difficulty still remains namely, the height at which the upper-level gravels stand above the

"Mém. Soc. d'Em. l'Abbeville," 1861, p. 475.

present water-line. We can not wonder that these beds have generally been attributed to violent cataclysms."*

In America, in Britain, and in Europe, the glacial deposits made clean work of nearly all animal life. The great mammalia, too large to find shelter in caverns, were some of them utterly swept away, while others never afterward returned to those regions. In like manner palæolithic man, man of the rude and unpolished flint implements, the contemporary of the great mammalia, the mammoth, the hippopotamus, and the rhinoceros, was also stamped out, and the cave-deposits of Europe show that there was a long interval before he reappeared in those regions. The same forces, whatever they were, which "smashed" and "pounded" and "contorted" the surface of the earth, crushed man and his gigantic associates out of existence.t

But in Siberia, where, as we have seen, some of the large mammalia were caught and entombed in ice, and preserved even to our own day, there was no "smashing and "crushing" of the earth, and many escaped the snowsheets, and their posterity survived in that region for long ages after the Glacial period, and are supposed only to have disappeared in quite recent times. In fact, within the last two or three years a Russian exile declared that he had seen a group of living mammoths in a wild valley in a remote portion of that wilderness.

These, then, good reader, to recapitulate, are points that seem to be established:

I. The Drift marked a world-convulsing catastrophe. It was a gigantic and terrible event. It was something quite out of the ordinary course of Nature's operations. II. It was sudden and overwhelming.

* "Prehistoric Times," p. 372.

"The Great Ice Age," p. 466.

III. It fell upon land areas, much like our own in geographical conformation; a forest-covered, inhabited land; a glorious land, basking in perpetual summer, in the midst of a golden age.

Let us go a step further.

CHAPTER VIII.

GREAT HEAT A PREREQUISITE.

Now, it will be observed that the principal theories assigned for the Drift go upon the hypothesis that it was produced by extraordinary masses of ice-ice as icebergs, ice as glaciers, or ice in continental sheets. The scientists admit that immediately preceding this Glacial age the climate was mild and equable, and these great formations of ice did not exist. But none of them pretend to say how the ice came or what caused it. Even Agassiz, the great apostle of the ice-origin of Drift, is forced to confess :

"We have, as yet, no clew to the source of this great and sudden change of climate. Various suggestions have been made-among others, that formerly the inclination. of the earth's axis was greater, or that a submersion of the continents under water might have produced a decided increase of cold; but none of these explanations are satisfactory, and science has yet to find any cause which accounts for all the phenomena connected with it."*

Some have imagined that a change in the position of the earth's axis of rotation, due to the elevation of extensive mountain-tracts between the poles and the equator, might have caused a degree of cold sufficient to produce the phenomena of the Drift; but Geikie says—

"It has been demonstrated that the protuberance of the earth at the equator so vastly exceeds that of any

* "Geological Sketches," p. 210.

possible elevation of mountain-masses between the equator and the poles, that any slight changes which may have resulted from such geological causes could have had only an infinitesimal effect upon the general climate of the globe." *

Let us reason together :

The ice, say the glacialists, caused the Drift. What caused the ice ? Great rains and snows, they say, falling on the face of the land. Granted. What is rain in the first instance? Vapor, clouds. Whence are the clouds derived? From the waters of the earth, principally from the oceans. How is the water in the clouds transferred to the clouds from the seas? By evaporation. What is necessary to evaporation? Heat.

Here, then, is the sequence:

If there is no heat, there is no evaporation; no evaporation, no clouds; no clouds, no rain; no rain, no ice; no ice, no Drift.

But, as the Glacial age meant ice on a stupendous scale, then it must have been preceded by heat on a stupendous scale.

Professor Tyndall asserts that the ancient glaciers indicate the action of heat as much as cold. He says:

"Cold will not produce glaciers. You may have the bitterest northeast winds here in London throughout the winter without a single flake of snow. Cold must have the fitting object to operate upon, and this object-the aqueous vapor of the air-is the direct product of heat. Let us put this glacier question in another form the latent heat of aqueous vapor, at the temperature of its production in the tropics, is about 1,000° Fahr., for the latent heat augments as the temperature of evaporation descends. A pound of water thus vaporized at the equator has absorbed one thousand times the quantity of heat which

"The Great Ice Age," p. 98.