SURFACE OF CLOUDS. 303 
TABLE XXXV.—Estimated Surface of Cloud, with reference to the Moon’s Age and Declination. 
After After 
Surface of || Moon’s | No. of | Surface of} Moon I Surface of |) Moon 
Cloud. Age. | Days. Cloud. |farthest 0 Cloud. || farthest 
North. North. 
14 
CHOTANRWNHYHO 
OOAONAaPwWNWr OS 
OPEN OSU ST 
or a ch we to Sw to ~F 
This Table has been formed from Table XXXIV. in the manner already indicated, Table X. 
Surface of Cloud, with reference to the Moon's Age.—The following means of groups indicate that the 
surface of cloud is a minimum about new moon :— 
. 12 days till 18 oY; Full Moon, 6:9 27 days till 3:days, New Moon, 6°5 
RDA ah. Soe 22 7-0 ON es Aa Zitat 6:7 
UG Bape D6. Fe: ek Aa Se oo onstrate 7:0 
2) Tansee ZONES. 6-9 Bile aoe 14 ... 7:0 
There is an appearance of a secondary minimum at full moon, but the differences of the means are very 
small.* 
Surface of Cloud, with reference to the Moon’s Declination.—The following means of groups seem to indi- 
cate that the surface of cloud is greatest a few days before the moon is farthest south, and least a few days be- 
fore it is farthest north :— 
25 days till : ae Moon farthest North, 6-6 11 days till 17 ei Moon farthest South, 7-3 
Ors nis 6:9 ee  ooccge 20 6-6 
4 odpnea 10 was 6-9 ey ooeens Wee Boe 6-7 
Th eae Cus 74 A | ae es 2 his 6:6 
Extremes of the Daily Mean Surface of Clouds for each Month, with the ranges of the monthly means, and 
number of days in each month wholly overcast :— 
Jan. Feb. March. April. May. June. July. Aug. Sept. Oct. Nov. Dee. 
Greatest, 10-0 10-0 10-0 10-0 10-0 10-0 10-0 10-0 9-2 10:0 10-0 » 10-0 
Least, 15 3-1 0-0 4-7 2-2 0:5 4-7 1-3 0-1 1-1 0-4 2-9 
Range, 8-5 6-9 10-0 5:3 7:8 9-5 5-3 8-7 9-1 8-9 9-6 7-1 
No. of Day: ” 2 6 3 2 9 6 3 1 0 1 1 I 
Overcast, 
The surface of clouds was 10-0 on nine days in the month of May, and in the month of September no day 
was quite overcast. Only on one day was the sky perfectly free of clouds, namely, on the 8th of March; on 
the 22d and 23d of September the amount was very small. 
* Tf the heat from the Moon have any effect on the dissipation or formation of clouds, it is obvious that the effect will be greatest 
during the night, when the Moon is about full; the want of observations from 9" P.M. till 54 a.m. would therefore vitiate the results 
more markedly than in previous cases investigated, where any effect of the Moon must be supposed sufficiently permanent to affect 
the means during the day as well as the night. 
