It follows from these experiments, that glacier-ice,
at a temperature of 32 deg. Fahrenheit, may change its form and preserve its
continuity during its motion, in virtue of the pressure to which it is
subjected. The statement is, that, when two pieces of ice with moistened
surfaces are placed in contact, they become cemented together by the
freezing of a film of water between them, while, when the ice is below
32 deg. Fahrenheit, and therefore _dry_, no effect of the kind can be
produced. The freezing was also found to take place under water; and the
result was the same, even when the water into which the ice was plunged
was as hot as the hand can bear.
The fact that ice becomes cemented under these circumstances is fully
established, and my own experiments have confirmed it to the fullest
extent. I question, however, the statement, that regelation takes place
_by the freezing of a film of water between the fragments_. I never have
been able to detect any indication of the presence of such a film, and
am, therefore, inclined to consider this result as akin to what takes
place when fragments of moist clay or marl are pressed together and thus
reunited.
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