246 Remarks on the Moving Rocks of Salisbury. 
although very firmly fixed in the stones and gravel. During 
the past winter the rocks have moved but very little, owiag 
to the mildness of the season. From December 1823, to 
February 1625, the rock above mentioned has moved twe 
and a half feet, which is much less than in former years, for 
the same reason; besides it has now become more deeply 
imbedded in the gravel, and the full force of the expanding 
ice is not exerted upon it. 
Since the attention of the public was called to this subject 
in 1822, many similar facts have been observed in different 
parts of New England. In the mountain pond in this town, 
the rocks within reach of the ice are annually moved toward 
the shore, forming an artificial dike of considerable extent. 
The same has been observed in ponds in Sharon and other 
laces. There is no longer any doubt or dispute on the 
subject, and the cause is as obvious as that of any natural 
sic aah which occurs. 
remarks on this subject by J. Wood, Esqu, i in the Jast 
Seiiber of the Journal are highly ingenious and plausible, 
; bo T Bi Bota hep ato by evidence. I have never 
rock” in the manner he nrentions, and 
the kit coritaing a greater portion of caloric than the water, 
the ice dissolves most rapidly nearest the shores of the 
pond.” { think it might with the same propriety be added, 
that as stone is 4 tolerably good conductor, the rocks serve 
as conducting media, conveying the caloric from the adjacent 
earth and water to the ice and surrounding atmosphere, thus 
melting the ice around their edges. At any rate, the moving 
rocks of this town are generally of such shape that they can 
not well be “ grasped” by the ice, being very shelving ; and 
that they are not supported in this manner, and thus driven 
about by the winds and waves, is evident from the fact, that 
thei ice thaws around them (it being near the shore) before it 
does in other parts of the pond. It is however undoubtedly 
true that rocks of considerable size are sometimes moved by 
large bodies of ice being driven forcibly against them. 
le expansive power of freezing water has been so ably 
treated by Mr. Adams in the last number of the Journal, that 
tis un ry to dwell upon it here. It has been found: 
from experiments performed at Edinburgh, to burst the 
