164 Association of American Geologists and Naturalists. 



action ? Might there not have been a period when the northern portion 

 of our hemisphere was covered with glaciers resembling those of the 

 Alps, during which the furrows were produced by their gradual and 

 radiolinear advance, followed by one of drifting ice, (whether borne 

 along with a sudden rush of waters, caused by a paroxysmal elevation 

 of land in the vicinity of the pole, or floods resulting from a gradual 

 melting away of the mass, he would not now pause to inquire,) depos- 

 iting bowlders through its course, and by the stranding and grinding of 

 large masses into beds of sedimentary matter or drift, have occasioned 

 the singular contortions visible in portions of the clay strata ? 



If it could be shown that a sudden and violent rush of waters from 

 the polar region had taken place, sweeping over the whole northern 

 portion of this hemisphere, bearing along with it large islands of ice, 

 denuding the hills and filling the valleys with drift, and eventually sub- 

 siding almost as rapidly as it poured southward, — would not this induce 

 a belief that the remarkable, large bowl-shaped cavities described in 

 Prof. Hitchcock's able memoir on the drift of New England, as existing 

 on Cape Cod and elsewhere, might have been formed by the stranding 

 and grinding of large islands of ice down into the recently deposited 

 drift ? It occurred to Mr. C. at once, when these excavations were 

 alluded to by Prof Hitchcock, in connection with ice, that they might 

 have originated in this manner, rather than from the deposition of mat- 

 ter round the melting ice, as suggested by that gentleman, — or they 

 may have been produced by a combination of these two operations ; the 

 grinding and settling down of the stranded berg, excavating a hollow, 

 while the earthy materials contained in it would be piled up round the 

 sides as it dissolved. If we supposed a very large berg of the pinna- 

 cled character, to have been left aground by the subsidence of the 

 paroxysmal flood, and divided into several smaller ones, each forming 

 a separate crateriform bed for itself, we should then readily compre- 

 hend the production of such a group of these cavities as was described 

 by Prof. H. Whether these suggestions were borne out by the geolo- 

 gical features of the drift in general, was left for those to determine 

 whose observation had been more specially directed to a study of these 

 phenomena. Mr. Couthouy observed that he would merely repeat that in 

 relation to the production of diluvial, or to speak more correctly, gla- 

 cial furrows, he had no preconceived views of his own to support, but 

 that when he first heard them attributed to the grating along the bottom 

 of icebergs, he was convinced by the recollection of what he had per- 

 sonally witnessed of the action of ice under such circumstances at the 

 present day, that this never would have produced such results. The 

 parallelism and uniform direction of the strise, appeared to him con- 

 clusive of a diffei'ent agency in their formation. He felt persuaded 



