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of hail. Hail, whether in summer or winter, is almost, if 
not invariably, accompanied with lightning. In the presence 
of these facts, it seems not unreasonable to consider the 
formation of hail as essential to great electrical storms ; 
although, as has been pointed out by Professor Thomson, 
very considerable electrical effects might be expected from 
the negatively charged air on the surface of the earth being 
drawn up into columns, and although, as the same 
philosopher has observed, every shower of rain gives the 
phenomena of a thunderstorm in miniature. The physical 
action of insulators and electrics in mutual friction must 
certainly produce very marked effects on the grand scale of 
nature. If we suppose that the falling hail is electrified by the 
air it meets, the electrification of the cloud into which the 
hail falls might thus be constantly increased until the balance 
between it and the inductively electrified earth is restored by 
a flash of lightning. If the hail is negatively electrified 
by the dry air with which it comes in contact, the latter 
will float off charged with positive electricity, which may 
account for the normal positive condition of the atmosphere 
in serene weather, as well as the electrification of the upper 
strata evidenced by the aurora borealis. The friction of 
wind has been supposed by Herschel to contribute to the 
intense electrification of the cloud which overhangs volcanoes 
during eruption. 
Dr. Thomas Alcock read a Paper “ On the Tongues of 
Mollusca.” [An abstract of this Paper will be found in the 
report of the Microscopical Section, Proceedings No. 12.] 
Dr. Crace Calvert stated that one of the difficulties 
which Dr. Alcock had encountered in his extensive and 
laborious researches, namely, that of preserving his specimens 
from putrefaction, would be overcome by the use of a saturated 
solution of pure carbolic acid, taking care that a small excess 
of this powerful antiseptic should also remain at the bottom of 
