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illustration which constitutes the frontispiece of this volume, and the foregoing engraving on page 93, he will see that the Drift is deposited on the earth, as it might have been if it had suddenly fallen from the heavens; that is, it is on one side of the globe—­to wit, the side that faced the comet as it came on.  I think this map is substantially accurate.  There is, however, an absence of authorities as to the details of the drift-distribution.  But, if my theory is correct, the Drift probably fell at once.  If it had been twenty-four hours in falling, the diurnal revolution would, in turn, have presented all sides of the earth to it, and the Drift would be found everywhere.  And this is in accordance with what we know of the rapid movements of comets.  They travel, as I have shown, at the rate of three hundred and sixty-six miles per second; this is equal to twenty-one thousand six hundred miles per minute, and one million two hundred and ninety-six thousand miles per hour!

And this accords with what we know of the deposition of the Drift.  It came with terrific force.  It smashed the rocks; it tore them up; it rolled them over on one another; it drove its material into the underlying rocks; “it indented it into them,” says one authority, already quoted.

It was accompanied by inconceivable winds—­the hurricanes and cyclones spoken of in many of the legends.  Hence we find the loose material of the original surface gathered up and carried into the drift-material proper; hence the Drift is whirled about in the wildest confusion.  Hence it fell on the earth like a great snow-storm driven by the wind.  It drifted into all hollows; it was not so thick on, or it was entirely absent from, the tops of hills; it formed tails, precisely as snow does, on the leeward side of all obstructions.  Glacier-ice is slow and plastic,

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and folds around such impediments, and wears them away; the wind does not.  Compare the following representation of a well-known feature of the Drift, called

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CRAG AND TAIL.—­c, crag; t, till.

“crag and tail,” taken from Geikie’s work,[1] with the drifts formed by snow on the leeward side of fences or houses.

The material runs in streaks, just as if blown by violent winds: 

“When cut through by rivers, or denuded by the action of the sea, ridges of bowlders are often seen to be inclosed within it.  Although destitute of stratification, horizontal lines are found, indicating differences in texture and color."[2]

Geikie, describing the bowlder-clay, says: 

“It seems to have come from regions whence it is bard to see how they could have been borne by glaciers.  As a rule it is quite unstratified, but traces of bedding are not uncommon.”

“Sometimes it contains worn fossils, and fragments of shells, broken, crushed, and striated; sometimes it contains bands of stones arranged in lines.”