[1.  “A Short American Tramp,” pp. 68, 107.

2.  Ibid., p. 68.

3.  Ibid., p. 72.

4.  Ibid., p. 76.

5.  “The Great Ice Age,” p. 391.

6.  “Narrative of Arctic Land Expedition to the Mouth of the Great Fish River,” pp. 140, 346.]

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away from each side of the valley of the Great Fish River, in north latitude 66°, of great height, and crowned with gigantic bowlders.

Why did not the advancing ice-sheet drive these deposits southward over the plains of the United States?  Can we conceive of a force that was powerful enough to grind up the solid rocks, and yet was not able to remove its own débris?

But there is still another reason which ought to satisfy us, once for all, that the drift-deposits were not due to the pressure of a great continental ice-sheet.  It is this: 

If the presence of the Drift proves that the country in which it is found was once covered with a body of ice thick and heavy enough by its pressure and weight to grind up the surface-rocks into clay, sand, gravel, and bowlders, then the tropical regions of the world must have been covered with such a great ice-sheet, upon the very equator; for Agassiz found in Brazil a vast sheet of “ferruginous clay with pebbles,” which covers the whole country, “a sheet of drift,” says Agassiz, “consisting of the same homogeneous, unstratified paste, and containing loose materials of all sorts and sizes,” deep red in color, and distributed, as in the north, in uneven hills, while sometimes it is reduced to a thin deposit.  It is recent in time, although overlying rocks ancient geologically.  Agassiz had no doubt whatever that it was of glacial origin.

Professor Hartt, who accompanied Professor Agassiz in his South American travels, and published a valuable work called “The Geology of Brazil,” describes drift-deposits as covering the province of Pará, Brazil, upon the equator itself.  The whole valley of the Amazon is covered with stratified and unstratified and unfossiliferous

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Drift,[1] and also with a peculiar drift-clay (argile plastique bigarrée), plastic and streaked.

Professor Hartt gives a cut from which I copy the following representation of drift-clay and pebbles overlying a gneiss hillock of the Serra do Mar, Brazil: 

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DRIFT-DEPOSITS IN THE TROPICS.

a, drift-clay; f f, angular fragments of quartz; c.
sheet of pebbles; d d, gneiss in situ; g g, quartz and
granite veins traversing the gneiss.

But here is the dilemma to which the glacialists are reduced:  If an ice-sheet a mile in thickness, or even one hundred feet in thickness, was necessary to produce the Drift, and if it covered the equatorial regions of Brazil, then there is no reason why the same climatic conditions should not have produced the same results in Africa and Asia; and the result would be that the entire globe, from pole to pole, must have rolled for days, years, or centuries, wrapped in a continuous easing, mantle, or shroud of ice, under which all vegetable and animal life must have utterly perished.