under pressure at Temperatures below 32° F. 435 
of the following year, some account of the work done in the 
winter preceding. On neither of these occasions were details 
of observations given to the press. The work was incomplete, 
and as even at my home in Vermont, the periods of extreme 
cold, lasting for two or three days, in which the most favorable 
opportunities are given for conducting such experiments, do 
not occur many times in any one winter, my work ran along 
until the spring of 1871. My note- books show an accumula- 
tion of numerous trials of the effect of pressure upon snow and 
ice, reed a portion of which will be included in this article. 
‘After the observations were ma e, a change of residence for 
a pris of years, took me away from Vermont to a region 
less favorable for such observations. Other occupations have 
also prevented me from putting the results into presentable 
shape. In the meantime, however, these results have not, so 
far as I know, been anticipated, and though they are not by 
any means as satisfactory as I could wish, the publication of 
them may at least save anyone else the necessity of going over 
the same ground. give first in order a series of experiments 
reunited under a moderate or even a heavy pressure. Also 
whether cold and dry snow will upon like circumstances of 
aie become converted into solid ic 
Thirdly, I have considered it desirable to nete whether the 
time acai intervenes as a factor, whether reunion and 
glaciation at low temperatures take place on reel or 
whether the Ate requires time for its complet 
nd in the fourth place, it is a matter of taabrask and per- 
haps of pavetioal bearing on theories of glacier motion, to know 
whether, in case such union of ice masses and snow lepapee 
ice retained at low temperatures. The supposition of regela- 
tion necessarily involves the development of moisture along the 
ice joint and among the snow granules. In the absence of 
eee moisture the result is to be ascribed simply to the molec- 
observation was Faraday’s, the term regelation was appt to the 
ieaarvel facts by Professor Tyndall. 
