446 FE. Hungerford—Observations on Snow and Ice 
the snow before alee In this way the 32° F. would be too- 
much and the 14° F. would be too little. From numerous 
observations, I am ane satisfied that the effect of pressure 
quietly applied, would not exceed a degree, or a degree and one- 
alf of Fahrenheit; and where special pains are taken to avoid 
sGietion of temperature, its effect will be so diminished that they 
may be left out of the account, in experiments conducted a 
number of degrees below freezing, If it is said that the 
method of taking the temperatures is crude, this must certainly 
be admitted. But it is the best that could be devised. I have 
indeed sashes a thin, hollow pointer of iron to the plunger, 
in the center of which I carried a thermometer down into the. 
snow and strove by this means, to get at the temperature dur- 
ing pressure. But after numerous trials, the indications proved 
o be so unreliable that I have discarded the results. It may 
te said, however, in favor of the proximate accuracy of the 
temperatures quickly taken after the pressure is removed, that, 
w is not elastic, the — evolved by pressure will not 
be absorbed again on its wit 1, 
So far as the observations ou they were entirely Saree 
tory of the above conclusion. The thermometrie evidenc 
being ree the supposition of any development of csnaen 
so arranged matters” that. f could actually watch the 
an inch in diameter in the opposite sides. These moulds were 
as usual in alte bolted, so that the eae, ice could be: 
expos ough a windows, which were of very heavy 
_ lass, 1 . watched he progress of worden from beginning 
a 8 signees scrutiny failed to disclose any signs of 
rohan ee any free and abundant nek of water through the 
would have been readily detec ‘without nice contrivances. 
We are considering only the production of a proper moisture, 
which might be forecd: through the mass so as who 
meate it. Of such moisture I found no trace the lowe 
temperature experiments. When the pressure had been an 
brought to bear, a change could be seen coming over the mass, 
as will be detailed ina ge hes below. The snow in the 
mould, as seen throug e glass, began to have a glaz 
rd ea and eat lies to be losing its whiteness and 
opac This'change went on gradually until the whiteness o 
the snow was nearly gone. I could discern upon the glass no 
trace of condensation of moisture, no clouding as if by a haar 
though the temperature of the room was only a few degrees 
above zero of Fahrenheit. 
