26 
DR. WOLLASTON’S METHOD OF COMPARING THE LIGHT 
IV. Reduction of the preceding observations of the Sun and Sirius. 
If all the light of the sun, which falls on the thermometer-bulb, be reflected 
by it, the light of 0 = x i ~l X tlie of Sirius ; and since 
there are seven observations of the sun compared with a candle, and seven of 
• • • 4 D X ^ X 5 X A 
Sirius, there will be forty-nine different values of the expression -- B x /3 x d x l ’ 
which are all inserted in the following Table. 
Observations of 0. 
1826. 
March 10. 
1827. 
March 2. 
1827. 
March 16. 
1827. 
March 16*. 
1827. 
March 25. 
1827. 
March 25*. 
1827. 
April 6. 
Totals. 
Of Sirius. 
1826, March 15 
.... March 19 
1827, Feb y 14 
.... Feb y 15 
.... March 1 4 
.... April 4 
.... April 9 
96.297 
73.560 
109.672 
75.789 
98.435 
86.854 
89-749 
107.022 
81.732 
121.886 
84.230 
109.397 
96.527 
99-745 
160.533 
122.629 
182.829 
126.345 
164.096 
144.791 
149.622 
127-441 
97-351 
145.141 
100.301 
127.630 
112.625 
116.366 
124.859 
95.398 
142.200 
98.268 
130.270 
114.944 
118.776 
91.668 
70.024 
104.400 
72.146 
93.703 
82.679 
85.435 
106.634 
81.458 
121.725 
83.925 
109-002 
96.178 
99-384 
814.454 
622.152 
927.853 
641.004 
832.533 
734.598 
759-077 
5.331.671 
Hence the mean result of the foregoing experiments is that, supposing none 
of the Sun’s light to be lost on reflection at the thermometer-bulb, 
O’s light = 108.809 2 X light of Sirius 
= 11.839.533.000 X the light of Sirius ; 
but, allowing for the loss of nearly half the light on reflection, that 
O’s light = 20.000.000.000 X the light of Sirius. 
