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numerous and deep, often extending for several feet, and in one case a 
continuous furrow was observed one hundred feet in length. The gene- 
ral direction of these scratches is N. N. E. and S. S. W.; sometimes 
there are slight variations from this course. The appearance of the 
scratches often indicates that they were produced by two boulders com- 
ing in contact, when the lighter one was moved out of its course, pro- 
ducing a furrow in the direction of the force applied. 
In pursuing these investigations, we are irresistibly led to the conclu- 
sion, that an oceanic current has flowed over the limestone terrace, from 
the Genesee to the Niagara river, and indeed over the whole western 
part of our State. Whether this ocean existed before or since the up- 
lifting of these rocks, perhaps we cannot determine; but appearances 
strongly indicate that the face of the country was the same as it now is. 
There are also many circumstances that would favor a conclusion that 
the current was from the south, passing over the surface of the limestone 
till it came to the softer shales and marls on the north, which are worn 
down, abruptly, at the termination of the limestone. The limestone, 
marked by these scratches, crops out on the north at the edge of the 
terrace, and from this point there is an abrupt descent over shales, soft 
sandstones and marls. The descent, from the top of this terrace to the 
level of the country on the north, at its eastern extremity, is about thirty 
feet, but in the western part of our district the descent is more than two 
hundred feet. 
Where the soil is removed from the polished and furrowed rock, we 
find resting upon it, in many places, an irregular deposit of pebbles and 
boulders, some of the latter of large size. These are frequently ce- 
mented by a gravel or hard pan, with infiltrated carbonate of lime. — 
Above this stratum we have clay, sand, and loam, with little or no coarse 
materials. These boulders are of various granites, limestone from the 
formation on which they rest and from the south, and siliceous sand- 
stone from the north. These materials all attest the action of violent 
currents, and not of a single and uniform current, but of opposite or con- 
flicting ones. The presence, in the same locality, of boulders from the 
north, with those from the south, proves that opposite forces have pre- 
vailed either at the same or at different periods. 
The extent of these diluvial formations, with the great numbers of 
erratic blocks, and the evidence of long continued wearing action on the 
limestone, prove that the force was not sudden and violent, but conti- 
nued for an indefinite period. If, then, we admit the presence of an 
