INTERPEETATION OF LAND FORMS 137 



third and fourth meetings of the Association of American 

 Geologists and Naturalists (1842, 1843) under the lead 

 of a committee on drift consisting of Emmons, W. B. 

 Rogers, Vanuxem, Nicollet, Jackson, and J. L. Hayes. 

 The result of these discussions was a curious reaction. 

 Hitchcock complained that he "had been supposed to be 

 an advocate for the unmodified glacial theory, but he had 

 never been a believer in it," and Jackson spoke for a 

 number of men when he stated: 43 



' ' This country exhibits no proofs of the glacial theory as taught 

 by Agassiz but on the contrary the general bearing of the facts 

 is against that theory. . . . Many eminent men incautiously 

 embraced the new theory, which within two or three years from 

 its promulgation, had been found utterly inadequate, and is now 

 abandoned by many of its former supporters." 



Out of this symposium came also the strange contribu- 

 tion of H. D. Rogers (1844), 44 who cast aside the teach- 

 ings of deduction and observation and returned to the 

 views of the Medievalists. 



' ' If we will conceive, then, a wide expanse of waters, less per- 

 haps than one thousand feet in depth, dislodged from some high 

 northern or circumpolar basin, by a general lifting of that region 

 of perhaps a few hundred feet, and an equal subsidence of the 

 country south, and imagine this whole mass converted by earth- 

 quake pulsations of the breadth which such undulations have, 

 into a series of stupendous and rapid-moving waves of transla- 

 tion, helped on by the still more rapid flexures of the floor over 

 which they move, and then advert to the shattering and loosen- 

 ing power of the tremendous jar of the earthquake, we shall have 

 an agent adequate in every way to produce the results we see, to 

 float the northern ice from its moorings, to rip off, assisted with 

 its aid, the outcrops of the hardest strata, to grind up and strew 

 wide their fragments, to scour down the whole rocky floor, and, 

 gathering energy with resistance, to sweep up the slopes and over 

 the highest mountains." 



Because of the prominence of their author, Rogers 's 

 views exerted some influence and seemingly received 

 support from England through the elaborate mathematic 

 discussions of Whewell (1848), who considered the drift 

 as "irresistible proof of paroxysmal action," and Hop- 

 kins (1852), who contended for "currents produced by 

 repeated elevatory movements." 



