G20 
THE EAEL OF EQSSE OH THE EADIATIOH 
Observations of the Moon’s light, November 14th, 1872. 
Sidereal time. 
I. 
Log sin 2 I. 
Log. corr. (<r). 
Zen.-dist. 
Moon’s app. 
semidiameter. 
(J)£», 
Moon’s light. 
h m 
O 
O 
, „ 
6 141 
49-5 
9*762 
9-997 
50-1 
15 40-0 
•045 
0-6368 
6 181 
47-5 
9-735 
9-997 
50-6 
15 40-0 
•047 
0-6012 
7 46i 
34-65 
9-510 
0-000 
62-4 
15 37-3 
•116 
0-4227 
7 50 
32-15 
9-452 
0-000 
62-9 
15 37-2 
•120 
0-3733 
8 281 
31-0 
9-424 
0-001 
68-5 
15 35-8 
•175 
0-3981 
8 331 
29-05 
9-372 
0-001 
69-2 
15 35-6 
•182 
0-3589 
8 371 
29-2 
9-377 
0-001 
698 
15 35-5 
•189 
0-3690 
*8 411 
23-95 
9-217 
0-001 
70-3 
15 35-3 
•195 
f 0-25881 
8 451 
29-5 
9-385 
0-001 
70-9 
15 35-2 
•203 
0-3882 
8 491 
31-4 
9-434 
0-001 
71-4 
15 35-0 
•210 
0-4416 
9 81 
29-35 
9-380 
0-002 
74-2 
15 34-2 
•253 
0-4295 
9 121 
27-6 
9-332 
0-002 
74-8 
15 34-2 
•264 
0-3963 
Interpolating the light-observations ancl multiplying them by the common factor 
764 - 9 to reduce them to the same scale as the heat-observations, the following compa- 
rison of the moon’s heat and light is arrived at. 
Comparison of the Moon’s Heat and Light. 
Sidereal time 
from middle 
of eclipse. 
Moon’s heat. 
Moon’s light. 
l-k. 
h m 
-2 11 
520-0 
477*6 
-42-4 
-0 39 
323-9 
309*0 
-14-9 
+ 0 6 
259-8 
295-2 
+ 35-4 
+0 19 
267-3 
299-3 
+ 32-0 
+ 0 40 
320-2 
309*8 
-10-4 
It may be well to add that although the thermopiles used on this day were the same 
as for the rest of the experiments, they had been remounted in the early summer, by 
which their sensitiveness was considerably increased. The allowance for the extinction 
of the moon’s heat in the atmosphere was made in accordance with the Table deduced 
in the earlier part of this paper, while that for the moon’s light was taken from 
Professor Seidel’s Table. 
Comparison of the Phase-Curve for Heat as given in this paper with that for Light deduced 
by Professor Zollxer from his and Sir Jonx PIerschel’s observations. 
A diagram (Plate XLVIIL, Curve C) accompanies this paper, on which is laid down 
the heat-curve and the determinations for the moon’s light, those marked Z and Z2 
derived from observations made by Professor Zo lexer by his first and second methods 
taken from the Table at p. 102 of the ‘ Photometrische XJntersuchungen,’ and those 
marked H derived from Sir John Herschel’s observations taken from plate iv. of that 
work. 
* Some mistake in reading the intensity-circle ; observation rejected. 
