ioo Mr. Herschei/s account of a series of observations 
July 19th. The fifth rocket could not be observed. 
Rockets. 
App* Time I. 
II. 
- III. 
Mean. 
1 
9 h 32 m 43 .i s 
- - 43 -° s 
- - 43.0s 
43 -° 3 s 
2 
- 42 41.Q 
- - 40.9 
- - 41.0 
4 o -97 
3 
- S 2 34 - 1 
- - 34 a 
- ~ 34-2 
34- 1 3 
4 
5 
IO 2 36.9 
■ 
- - 36.9 
- - 36,9 
36.9 
6 
- 22 42.9 
- - 42-9 
- - 42.9 
42.9 
7 
- 33 4-8 
- - 4.7 
4 -75 
8 
- 42 40.x 
- - 40.0 
- - 40. 2 
40.1 
9 
. - 52 40.0 
- - 40.0 
- - 39-9 
39-97 
IO 
::ix 2 43.3 
: : “ 43-1 
- - 43-7 
43-7 
Comparison of Chronometer and Clock. 
Chronometer. 
Clock. 
Before 8 h 48“ 
x6 h 3 6 m 53.84 s 
After j x x 0 
18 59 17.02 
Mean Error and Rate of Sidereal Clock. 
Mean of 3 * s 
i6 h 50“ 
Megn error, 
47-i 6s 
Mean rate. 
— 0.19 s 
Comparison from 18th to 19th — 1.81 
Chronometer fast i m 16.26s 
Observation 10 in columns 1 and 2 doubtful to half a second. 
