Sharpless. ] 
quent work. 
square is 0.//14. 
80 
[April 6, 
The probable error of this mean by the method of least 
The value of a level division was obtained by placing the movable mi- 
crometer wire on a terrestrial mark, and taking the reading, and again 
after the instrument was changed in altitude so as to cause the bubble to | 
to move through a certain number of divisions. 
ards reduced to dacond. 
revolutions, which were afterw: 
large number of determinations gave, 
The stars used were taken from the Nine Years Catalogue of Greenwich 
Observatory for 1872, 
the mean declinations 
This gave it in micrometer 
The 
result, of a 
as the most probable value, 6//.3. 
calculated for the epoch 
1881.0, 1882.0, or 1883.0, and the apparent declinations for the night of 
observation were obtained by the use of the ‘‘independent star numbers’ 
of the American Nautical Almanac. 
The results were as follows : 
Catalogue 
Date. No, of Stars, 
% (8 
ooo 
a 
AD 
a 
> SUS 
an 
a 
one S 
= 
ot 
DX 
ea 
ea) 
82/799 
56,29 
22.00 
58,60 
59.76 
59,645 
15.578 
57,82 
44,92 
44,923 
57.46 
44,92 
44,79 
56,818 
46.794 
51.519 
| Correction, 
| a 157.85 
54, 495 
50,248 
Micrometer 
Level Cor- 
rection. 
| 
6.72 
b 1018 
8.1 .| 
== 
PIN DAOEEH 
a 
rt 
te 
gS 
SNP RS 
| 
wns 
RR Ot 
‘ 
= 
a 0’ 
Latitude. 
10/742 
12.84 & 
