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SUPPOSED GLACIATION OF BRAZIL.
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Thomas Belt, the author of The Naturalist in Nicaragua, says in that volume[1] that though no ice marks are visible he has seen "near Pernambuco, and in the Province of Maranham, in Brazil, a great drift deposit that I believe to be of glacial origin."

I have seen and studied the deposits to which Belt refers; my opinion is that while they bear a certain resemblace to glacial drift they are entirely devoid of positive evidence of glacial origin. The method of their formation is explained in another part of this paper.[2]

AGASSIZ'S CHANGE OF VIEWS.

It is appropriate that I here quote from Professor N. S. Shaler, a former pupil of Professor Agassiz:[3]

"There has been a good deal of discussion concerning the former existence of glaciers in the valley of the Amazon. Agassiz, to whom we owe the first suggestion of the value of glaciation as a great geological agent, at one time thought it likely that the valley of this great river had been the seat of a glacier that poured its ice from the Andes nearly down to the sea. This, which was hardly more than a suggestion put forth for the discussion of geological students, was, I believe, practically abandoned by this illustrious naturalist before his death, (In this assertion I have embodied the results of several remarks by my late master on this subject made during the last two years of his life. It is satisfactory to know that the only considerable mistake he made in the matter of glaciation was corrected by his own reflections on the subject. N. S. S.) and has been found to be an essentially mistaken view. The late Professor Hartt, geologist of Brazil, at one time thought some of the debris in the mountain districts near Rio de Janeiro was of glacial origin, but this suggestion has never been submitted to discussion, and can have no weight against the other evidence of a negative kind that goes to show that glaciation, save in higher mountain countries, has never extended into the intertropical regions."

  1. ↑ The Naturalist in Nicaragua, by Thomas Belt, F.G.S., 2d ed.London, 1888, 265.
  2. ↑ It has been asked how I reconcile Belt's statements regarding glaciation in Nicaragua with my inability to find trustworthy evidence of glaciation at a similar south latitude. I don't try to reconcile them; I am simply dealing with the facts as I know them in Brazil. I have never seen Nicaraguan deposits, but I can't avoid suspecting that they will turn out like the Brazilian ones, J. Crawford's moraines and "moutonnéd ridges" to the contrary notwithstanding. (Proc. Amer. Assoc. Adv. Sci., XL., 265, and Science, XXII., No. 263, p. 270).
  3. ↑ Glaciers, by N. S. Shaler and W. M. Davis, Boston, 1881, 47.
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