346 
GEOLOGY OF THE FOURTH DISTRICT. 
This deposit of clay and quicksand extends about one hundred feet above the level of the 
canal, where it is succeeded by sand and gravel. For more than two hundred feet from the 
bottom, the mass consists of alternating layers of sand from two to eighteen inches, with layers 
of clay of half an inch to two inches, each becoming thicker as we approach the upper part, 
where the quicksand layers are fifteen and twenty feet. 
The upper layer, of fifteen feet thickness, becomes perfectly saturated with water, and is 
termed liquid quicksand; and this is succeeded by the deposit of coarse sand and gravel, 
which is of subsequent origin, containing materials from the rocks of the south, mingled with 
some of the older drift deposits which have been broken up. Through this the water perco¬ 
lates, saturating the mass below, and giving it the character of quicksand. 
Fragments of the trunks of trees have been found in this deposit, in a layer of clay about 
thirty-five feet below the gravel.* 
The whole of the lower deposit, consisting of regularly alternating layers of clay and sand, 
was evidently deposited in a quiet lake, while the subsequent one of gravel and coarse sand 
was brought on by some powerful inundation from the south. The fragments of wood are 
doubtless such as were drifted from the higher grounds into this lake, and sinking to the 
bottom, were covered by the subsequent sediment. 
In several similar situations, bones of the mastodon have been found, and consequently 
referred to the period of the drift. These facts, however, offer no arguments in favor of such 
an hypothesis ; for in all instances which occur in Western New-York, there is the strongest 
evidence of their having been transported from their original situation, and mingled with the 
more modern fluviatile or lake deposits. 
Another circumstance to be noticed in connection with this section, is a superficial deposit 
( a , b, c) of about ten feet in depth, covering the whole slope, from the base of the gravel hill 
to the bank of the river. This surface deposit is composed of the ruins of the gravel hill, 
with the clay and sand below. From the constant oozing of water from the lower deposit, 
it undermines that above, which falling, carries with it something of those below, the whole 
constituting a moving mass, saturated with water. Its nature only became fully under¬ 
stood upon the excavation of the canal, when all that part above commenced sliding down, 
completely destroying the work. Farther examination proved that the whole hill side, for 
ten feet in depth, was in motion towards the river, and of course no excavation or fixture 
could be made permanent on such a foundation. In proof of this, and that such, for a long 
period, has been its condition, we find that the oaks which grow upon the hill, towards the 
top, have slidden down to the rocky margin of the river, where they stand among the hem¬ 
locks and cedars, sometimes upright, but often leaning in various directions. 
* I am indebted to Col. Elisha Johnson, of Hornby Lodge, Portage, for numerous facts relating to this section, as well as for 
specimens of the wood, which was dug out under his direction. This wood has been examined by Prof. Bailey, of West-Point; 
but from its condition, he has been unable to decide its nature. 
