Sun’s observed and computed right ascensions, &o. 459 
Table VII. — continued. 
Exposure of the Instrument, September 25. 
The Sun’s rays were allowed to fall upon the instrument, 
sixty-three minutes before his centre came to the meridian ; 
other observations prevented me, attending to the thermo- 
meters ; the sky cloudless. 
Exposure of the Instrument, October 21. 
Times of Comparison. Thermometers under the cover Thermometers under the cover 
jj # of the Black, or Western Axi3. of the White, or Eastern Axis. 
12 56 50°.0 50°.0 
13 9 
59-o 
13 i° 
13 12 
*3 l 9 
13 2 3 
1 3 2 7 
l 3 45 
5i -5 
5 1 -5 
5 1 -7 
52 .0 
52 .2 
52 .5 
53 -5 
Mean rz 64 .6 Mean = 52 .1 
Hence, difference of temperature — 
Thermometers placed under the covers of the black and white braces, did not vary 
half a degree, from those applied to the cones of the axis. During the observa- 
tions, not a cloud was visible. 
Exposure of the Instrument, October 22. 
Times of Comparison. Thermometers under the cover Thermometers under the cover 
jj mi of the Black, or Western Axis. of the White, or Eastern Axis. 
12 56 5i°.o 5i°.o 
13 6 
1 3 12 
13 
13 20 
13 22 
13 24 
1 3 26 
13 46 
64 .0 
65 .0 
67 .0 
68 .5 
71 .0 
73 -8 
74 -5 
76 .0 
52 .5 
53 
53 -5 
53 -8 
54 
54 -o 
54.! 
54 -8 
Mean =: 70 .0 Mean — 53 .7 
Hence, difference of temperature = i6°.3. 
Thermometers under the covers of the black, and white braces, afforded results 
differing from the above, only a small fraction of a degree. 
