“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 contribution of H. D. Rogers (1844),[[48]] who cast aside the teachings of deduction and observation and returned to the views of the Medievalists.
“If we will conceive, then, a wide expanse of waters, less perhaps 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 earthquake pulsations of the breadth which such undulations have, into a series of stupendous and rapid-moving waves of translation, helped on by the still more rapid flexures of the floor over which they move, and then advert to the shattering and loosening 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 Hopkins (1852), who contended for “currents produced by repeated elevatory movements.”
After his arrival in America (1846), Agassiz’s influence was felt, and his paper on the erratic phenomena about Lake Superior (1850),[[49]] in which he called upon the advocates of water-borne ice to point out the barrier which caused the current to subside, produced a salutary effect; yet Desor (1852)[[50]] states that in the region described by Agassiz “the assumption [of a general ice cap] is no longer admissible,” and that the bowlders on Long Island “were transported on ice rafts along the sea shore and stranded on the ridges and eminences which were then shoals along the coast.” Twenty years of discussion were insufficient to establish the glacial theory either in Europe or America. The consensus of opinion among the more advanced thinkers in 1860 is expressed by Dana:[[51]]
“In view of the whole subject, it appears reasonable to conclude that the Glacier theory affords the best and fullest explanation of the phenomena over the general surface of the continents, and encounters the fewest difficulties. But icebergs have aided beyond doubt in producing the results along the borders of the continents, across ocean-channels like the German Ocean and the Baltic, and possibly over great lakes like those of North America. Long Island Sound is so narrow that a glacier may have stretched across it.”
Papers in the Journal of 1860–70 show a prevailing belief in icebergs, but the evidence for land ice was accumulating as the deposits became better known, and in 1871 field workers speak in unmistakable tones:[[52]]
“It is still a mooted question in American geology whether the events of the Glacial era were due to glaciers or icebergs.... American geologists are still divided in opinion, and some of the most eminent have pronounced in favor of icebergs.
Since, then, icebergs cannot pick up masses tons in weight from the bottom of a sea, or give a general movement southward to the loose material of the surface; neither can produce the abrasion observed over the rocks under its various conditions; and inasmuch as all direct evidence of the submergence of the land required for an iceberg sea over New England fails, the conclusion appears inevitable that icebergs had nothing to do with the drift of the New Haven region, in the Connecticut valley; and, therefore, that the Glacial era in central New England was a Glacier era.”
Matthew (1871)[[53]] reached the same conclusion for the Lower Provinces of Canada. In spite of the increasing clarity of the evidence, the battle for the glacial theory was not yet won. The remaining opponents though few in number were distinguished in attainments. Dawson clung to the outworn doctrine until his death in 1899.