86 
The last two days cannot be looked upon as very exact, 
as the condition of the snow changed so much. 
Besides these measurements made in the warmest part of 
the day I found the loss from — 
Feb. 5th, 9 a.m. to Feo. 7th, 9 a.m. to be OT 6 mm. 
„ 22nd, 3 p.m. to Feb. 23rd, 9 a.m. to be 0-28 mm. 
„ 26th, 9 a.m. to Feb. 27th, 9 a.m. to be 0’67 mm. 
„ 27th, 3 p.m. to Feb. 28th, 9 a.m. to be 048 mm. 
April 3rd, 3 p.m. to April 4th, 9 a.m. to be 043 mm. 
„ 4th, 3 p.m. to April 5th, 9 a.m. to be 062 mm. 
„ 5th, 3 p.m. to April 6th, 9 a.m. to be 043 mm. 
As the snow cannot be materially warmed the evaporation 
can never be very rapid from it, but this is quite different 
with the earth as soon as it is uncovered, as being dark it 
absorbs the heat and becomes very much warmed, causing 
rapid evaporation, so that where no fresh supplies of water 
are coming into the earth we may see it in a few days as dry 
as mummy dust. In order to see exactly how this takes 
place I propose next winter to bury a tin full of damp earth 
in earth of the same temperature and moisture. 
I this winter made some preparatory observations by 
putting some very damp earth into my tin and burying it 
in the snow in the same way as I had done when it was full 
of snow, but as the tin was too large to weigh when full of 
earth I was only able to partly fill it, which would 
materially affect the exactness of the observation. The 
earth was, of course, kept cool by the snow, whereas if it 
had been surrounded by earth, it would have been warmed. 
March 18th, added about 1 kilo water to about 4 kilos 
very dry earth ; lost from 9 a.m. to 3 p.m. 106 mm. of water. 
March 26th, lost from 9 a.m. to 3 p.m. 1T3 mm. of water. 
I would specially call attention to the evaporation of the 
snow during the day time, on April 2nd and 3rd, both of 
which were days of genuine snow melting, and it will be 
