252 ON THE LIGHT OF THE MOON AND OF THE PLANET JUPITER. 
April 2d. Perfectly clear. No clouds visible through the evening. 
ft. 
8 19 Sid. time. Venus. Diaphragm Z. d — 45.8 
DI [11 Di [14 di = 44.5 
Owing to moonlight, the image of 
8 29 s: Jupiter. S d Jupiter had become too E d" = 64,5 
for a reliable comparison. 
8 49 eg Moon 114 days old. Lamp, diaphragm X, without screen. d = 3.20 
« ve « « dss 313 
Di Di Di Di d = 3.60 
8 54 E " " go AAL 
'The above observations on the Moon must be corrected, as on March 30th, by the co- 
efficient y. Later in the evening the lamp I was placed in position as used for Venus 
and Jupiter, with the screen, but having no diaphragm ; the flame adjusted to a height 
of 0,75 from wick, and subsequently compared with standard, gave 
Z 
: = 7.8054. 
E Lamp-flame 0'".75 
h m ft. 
12 59 Sid. time. Moon with lamp J, as above. d — 144 
y s E 
April 5th. A thin haze about the horizon, with cirrus cloud. The sky near the 
Moon appeared clear, though not perfectly transparent. Lamp I in usual position, 
flame adjusted to a height of 07.96, and subsequently compared with standard. 
Log: o 0^96 — DEM 
k m $ ft 
11 33 Sid. time. Moon with lamp J, as above. d = 17.9 
11 36 in e « «o dx 192 
11 39 e E e ei d 19.8 
April 6th. Clear. ! 
Lamp S in usual position. Low flame. By comparison with standard, 
Z 
Log. Lap $ == 7.6954, 
d uw | ft 
14 39 Sid. time. Moon near meridian ; one day past full. d = 18.0 
Di se Di Di d = 13.8 d 
Di “ Di & d = 13.4 
“ “ “ “ d — 13.7 
e 3 S E d — 13.8 
