318 Rogers's Account of two Remarkable 
floating icebergs the agents in the dispersion of these erratics. 
He justly asks, By what agency could the blocks be raised upon 
the backs of the icebergs ? How could one large iceberg have 
loaded itself with enough of these huge fragments to strew 
the ground, as thickly as we see, for so many miles; and who 
will believe that successive icebergs could tear off and bear 
away successive blocks in precisely the same direction, so as 
to lengthen out the train? But there are other difficulties 
besides these which here suggest themselves. If we suppose, 
with Mr. Lyell, the surface of all the land now covered with 
the drift to have been submerged below the sea, it is obvious 
that only the advanced edge of the base of a drifting iceberg, 
striking the summit of the Canaan ridge, could load itself with 
any fragments. But, in this case, even if it could gather a - 
sufficient freight, there seems to be no adequate cause pro- 
posed for the linear and uniform scattering of the blocks, be- 
ginning with the very spot where they were just caught up. 
The dropping or spilling of boulders and soil from the surfaces 
of icebergs, is due, we know, to a gradual melting, chiefly, of 
the portions not immersed, while, in this imaginary case, the 
parts sustaining the boulders, being low in the water, would, 
certainly, not nielt fast enough to cause so copious a deposition 
as we see. But there is another difficulty. The top of the 
Taconic range is higher, as we have seen, than the source of 
the blocks in the Canaan ridge, and any iceberg, sunk deep 
enough to impinge upon the latter, would have found its pro- 
gress to the south-east effectually arrested by this higher 
barrier. To this latter objection it is not sufficient to reply, 
that the main Taconie ridge may have gained its present 
superior elevation, since the dispersion of the erratics, during 
a supposed subsequent slow rising from the sea of all this drift- 
covered region. Such answer would be equivalent to the as- 
sumption of an anticlinal bulging of the crust, under not only 
the Richmond and Lenox ridges, but beneath the still loftier 
Beartown chain; whereas the uniformity in the dip of the 
folded strata, in the two first ridges and their included valleys, 
