oem 
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Remarks on the moving of rocks by Ice. 145 3 
from the shore on all sides, and is thus converted into an 
island, moored by the roc 
The earth on which they rest, being soft mud, much > 
less power is requisite to raise them from their beds, or to 
project them along on this slippery surface, than would 
required to raise or move them on dry, stony, or gravelly 
ground. By the abundant rains of the spring, and 
dissolution of the snow and ice, the water of the pond is 
accumulated, whereby the island of ice, with every thing 
which remains attached to it, is raised until its strength is 
overpowered by the pressure. And we now that a single 
rood of ice of but a few inches in thickness will sustain 
an immense weight while lying on the surface of the 
water. 
A strong wind then, blowing from any “ers will 
agitate the water between the shore and the as also 
that under the ice. Thus the increase of the water, or 
the raising of the surface of the pond, will loosen, o 
tract from their beds all those rocks whose weight and 
depth in the earth are not too great for the strength of the 
ice; and the force of the wind, acting upon the water and 
the. ice, will propel them toward the opposite shore.— 
Like the ship therefore, whose anchor is unable to sustain’ 
the force of the tempest, the floating island is driven from 
its moorings. Thus forced toward the shore, the ice 
gradually dissolves on the side nearest the land, so that 
the rocks ~ attached to the ice, and partially resting in 
the mud, are dragged nearer and nearer to the shore, 
propelling ‘i mud before them, until the island be- 
comes so diminished, that with the power of the wind 
and the waves, it can no longer drag its anchors, and 
therefore deposits them near the margin of the pond. It 
is therefore a natural consequence that they oat a track 
behind them by which their progress may be tra 
If this exposition is not the true eo it mia at "east, 
answer until a better one can be given 
Vou. IX.——No. 1. 19 
