ASSOCIATION OF AMERICAN GEOLOGISTS. 
35 
on this subject, and was followed by Mr. lledfield, who stated 
that he had been led_, from his limited observations, to infer that 
the di'ift of the region near New York was the joint result of gla- 
cial and aqueous action, and was mainly deposited during a pe- 
riod of increasing submergence. He alluded also to the agree- 
ment of the strise of the polished rocks, and of the transported 
boulders and drift, with the known cause of the existing polar 
currents of the ocean, in the northern hemisphere; and sug- 
gested that this system of currents, being essentially the same 
in both hemispheres, and having its cause in the dynamics of 
the solar system, must have operated through all time, and over 
extensive regions, but varying in locality and direction with the 
changes of outline and relative levels of seas and continents, 
during the successive geological epochs. 
Some remarks were next made as to the origin of mounds in the 
western states, which we omit, as little connected with geology. 
Mr. Couthouy read a paper " On Icebergs." 
The first he had observed was on May 28th, 1822, in lat. 42° 
10' N. and 44° 50' W. long. (Greenwich), this was visible for 
eighteen miles. The second was on the eastern edge of the 
great bank of Newfoundland, lat. 43° 18' N., long. 48° 30' W. 
Thirdly, numerous others were met with by him in the summer 
of 1827, between the 36th and 42nd parellels of north latitude. 
A large ice-berg was also seen by him in August, 1827, 
in lat. 46° 30' N. and long. 48° W. stranded in eighty fa- 
thoms water. Large masses of rock and quantities of earthy 
matter were imbedded in its sides j and the water for at least a quar- 
ter of a mile round it was full of mud, stirred up from the bottom 
by the violent rolling and crushing of the mass ; this movement 
was accompanied by a harsh grating noise, with occasional crack- 
ing reports, audible for ten or twelve miles. 
In 1831 he had met with several small icebergs in lat. 36° 
20' N. and long. 67° 45' W. which from their proximity to each 
other were evidently portions of a larger one, it having been 
