No. 200.J 
309 
ocean covering the continent or a part of it, we should also admit the 
condition of an ocean as we find it at the present time. 
In the Atlantic, we have the ebb and flow of the tides, which, with 
violent winds, are sufficient to remove detritus in considerable quanti- 
ties. This action is much more violent in some places than in others; it 
is also alternate and opposite. We have also equatorial and polar cur- 
rents: The one in the gulf stream transporting light materials from the 
equatorial regions to mingle with the coarser materials brought^rom the 
north on islands of ice by the polar current. At the meeting of these 
currents the materials of both are gradually precipitated as the op- 
posing forces neutralize each other. The ice islands, as they are dis- 
solved by the warm current from the south, would precipitate their im- 
mense loads of northern matter to the bottom of the ocean, in a line 
corresponding to the course of the current. Each current, too, is con- 
stantly depositing along its course the heavier materials, carrying for^ 
ward those only, which require less force as the current is diminished in 
velocity from the resisting medium. Under these circumstances, we 
may perceive, that we would sometimes have a deposit, mostly, or en- 
tirely, from one quarter of the globe; and at others, from the opposite 
one, and in many cases from both directions. The banks of Newfound- 
land and St. George, are probably depositions from the two opposite 
currents, and in these deposits we may find materials from very distant 
quarters of the globe. May not some of our diluvial deposits have re- 
sulted from similar currents? The agency of running water, in produc- 
ing our diluvial deposits, is very obvious, and acknowledged by every 
one, but the effects have been ascribed to a current from one direction, 
and that from the north. We have thus overlooked the necessary con- 
siderations of opposite currents, arising from an ocean resting over our 
continent. 
In many cases we find the coarser materials on the southern slope of 
the hills, and the ascent in that direction more abrupt than on ihe 
north. We find, in many places, large numbers of granite boulders in 
the same deposit with those of limestone, the latter, either from strata 
directly beneath, or from those farther south. When the limestone frag- 
ments are from the stratum directly beneath, they are much more worn 
and rounded than we could expect, unless they had been whirled in the 
eddies of the passing currents, and suffered wearing action from trans- 
ported matter. It is very obvious, too, that the cause which transported 
the granite boulders from the northern regions did not effect in the same 
manner the limestone and other strata of western New-York.; for al- 
