OF A NORTH-WEST PASSAGE. 
167 
once more rose, and by eight A.M. stood at + 10°. On the two following 1820. 
days Captain Sabine made some observations on the difference in the tern- 
perature of the atmosphere in the sun, and in the shade ; which shew the 
effect of the sun’s rays much more correctly than those made on board, as it 
is almost impossible to prevent the thermometer from being affected by the 
radiation of heat from the ship. “ Two posts having been fixed in the snow, 
at a short distance apart, and connected by a line passing through the 
shadow cast, by the observatory, about the middle of the day, two mercurial 
thennometers, being an exact pair, and having their bulbs unprotected, were 
suspended from the line, one being exposed to the sun, and the other in the 
shade of the observatory ; the bulbs of both were six or eight inches from 
the snow.” 
h. m. 
SUN. 
SHADE. 
April 26, 
1 30 P.M. 
o / 
+ 17 
o • ^ 
-f- 6 5 
2 — 
22 
7 1 
/ Calm. 
2 13 
23 
^ ( 
2 18 
24 5 
7 6 j 
2 35 
20 5 
6 5 
A gentle air. 
2 50 
21 
6 7 
6 — 
9 5 
4 5 
April 27. 
11 20 A.M. 
15 
5 " 
11 30 
20 
7 
H 40 
34 
9 
11 45 
23 5 
8 5 
11 55 
24 
8 5 
) Almost calm. 
0 25 P.M. 
21 
7 
1 — 
20 
7 5 
2 20 
25 
7 7 
2 45 
10 
4 5 
A breeze sprung up. 
The morning of the 27th being very fine, and the thermometer at + 6°, xhur. 27. 
the ship’s company’s bedding was hung up to air, between the fore and main 
rigging, being the first time we had ventured to bring it from the lower deck 
for nearly eight months. While it was out, the births and bed-places were 
fumigated with a composition of powder mixed with vinegar, and known 
familiarly by the name of devils; an operation which had been regularly 
gone through once a week during the winter. 
