80 



sist of a single kind of rock, identical with that in the crest of the 

 ridge whence they originate. 



After exhibiting the inadequacy of either the iceberg or glacier 

 hypothesis to account for their production, the authors proceed to 

 show how all the phenomena may be explained by the theory 

 they have elsewhere advocated, of a sudden discharge of a portion 

 of the Arctic Ocean southward across the land. They discuss 

 the important functions of the wave of translation, show its sur- 

 passing velocity and great propulsive power, and trace the in- 

 fluence of vehement earthquakes near the Pole, in dislodging the 

 northern waters and ice, and maintaining in the rushing flood, 

 these vast and potent waves. They then suggest that, at a certain 

 stage of the inundation, the ice, previously floating free, would 

 impinge with irresistible violence against the tops of the submersed 

 hills, and that the Canaan mountain stood precisely in the position 

 to take the brunt of a part of the ice-driving flood, as it swept 

 down the long high slope of the distant Adirondack, and across 

 the low, broad valley of the Hudson. 



They next proceed to show that, at the instant when some 

 enormous ice-island struck the crest of the mountain, and scooped 

 the trench which we there behold, a great vortex was produced by 

 the obstruction, thus suddenly thrown in the path of the current, 

 which, endowed with an excessive gyratory or spiral velocity, was 

 capable of sustaining and carrying forward the greater part of the 

 fragments. As in the instance of the waterspout and whirlwind, 

 the functions of whose motion they discuss, the whirlpool would 

 gather into the rotating column the projected blocks, and strew 

 them in a narrow path, in the line along which its pendant apex 

 would drag the ground. 



The paper terminated with an application of this idea in detail, 

 to the explanation of each important feature of these Trains : to 

 their deflections from a straight line, the intermission in the bould- 

 ers at certain places in the Train, and to the fact that some of the 

 blocks have been violently broken at the moment previous to their 

 final rest. 



The paper was referred to the Publishing Committee. 



Mr. Bouve exhibited, and remarked upon, a beautiful col- 

 lection of tertiary fossils, recently presented by M. Tuomey, 



