88 
Mr. Herschel’s account of a series of observations 
Mr. Herschel's observations of the signals seen from Fairlight. 
Third Day, July 13, 1825. 
No. 
ll. ID. s. 
Remarks. 
La Canche 
A thick sea-fog suddenly came 
on 2“ before the time, though 
perfectly clear till then. 
Wrotham 
9 31 6-o:: 
A mere suspicion. Fog thicker. 
La Canche 
Fog. 
Wrotham 
Fog. 
La Canche 
Fog. 
3 
Wrotham 
9 5 1 I2 '5 
Very faint, but distinct. Fog clear- 
La Canche 
q q6 Z7‘6 
Distinct. [ing. 
4 
W rotham 
Object-glasses examined. All co- 
veredwith moisture from the fog. 
La Canche 
10 6 28-5 
Well observed. Train seen. 
5 
Wrotham 
10 11 16-5 
Perfectly well seen. 
C 
La Canche 
10 16 1 8* 1 
O 
Wrotham 
ic 21 1 4’ 1 
Well seen ; but the glass dim, and 
the fog coming on again. 
La Canche 
Fog suddenly came on again, and 
7 
Wrotham 
is surprisingly dense, so as 
O 
La Canche 
scarcely to allow the Mill to be 
O 
seen ; yet the stars are clear to 
within 10 degrees of the ho- 
rizon. 
Wrotham 
Fog. 
9 
La Canche 
• 
Fog. 
Wrotham 
Fog. 
IO 
La Canche 
Fog. 
Fourth Day, July 14, 1825. 
No. 
h. m. s. 
Remarks. 
La Canche 
9 26 22*7 
Very distinct; train seen. 
Wrotham 
9 3 i I 5 ‘ I 
A pretty strong breeze. 
La Canche 
9 3*5 15-3 
Train perfectly well seen. 
Wrotham 
La Canche 
9 41 16-4 
9 46 28-1 
Train seen. 
3 
Wrotham 
9 5 1 I 5 ' 2 
La Canche 
9 5 6 i 74 
Train seen Wind increasing. 
4 
5 
Wrotham 
La Canche 
Wrotham 
10 1 1 5*4 
10 6 ai’5 
10 11 19-6 
La Canche 
10 16 247 
• 2 3 s -S — am almost sure 2j s -^ is 
Wrotham 
10 21 1 8*8 
the right. 
7 
La Canche 
Wrotham 
10 26 25*0 
IO 3I I5’2 
Exploded irregularly at half its 
8 
La Canche 
10 36 17-5 
height. 
Train not seen. N. B. A star in 
Wrotham 
10 41 18-5 
the field of the glass. 
La Canche 
10 46 27-8 
First a bright spark; then the 
9 
Wrotham 
10 51 1 6-6 
train ; then long after, a feeble 
10 
La Canche 
10 t;6 iq-7 
explosion at 27% 8. The first 
flash was brighter than the ex- 
plosion. 
T rain feebly seen. 
Wrotham 
11 1 17-8 
Fifth Day, July 15, 1825. 
No. 
h. m. s. 
Remarks. 
1 
La Canche 
9 26 30-4 
The first flash seen at 19 s . 4 on 
lighting the rocket. The flash 
Wrotham 
9 3 i 22 '3 
at 3 o 9 ’4 very bright. 
2 
La Canche 
9 3 6 2 3'4 
Fainter than the 1st flash of No. 1. 
Wrotham 
9 4 1 2 3 ‘ 2 
A slight flash at lighting. The 
rocket did not rise. 
3 
La Canche 
Wrotham 
9 46 24' 2 
A flash at 1 6 S *3 low down. The 
flash at 24 s - 2 higher, and to the 
right of the former. (The teles- 
cope inverts. N. B.) 
La Canche 
q 2^-2 
Faint, but very distinct. 
4 
Wrotham 
10 1 18-0:: 
5 
La Canche 
10 6 23-5 
( Signal regular and distinct, but 
J observation uncertain from a 
Wrotham 
10 11 23-4 
10 16 1 8- 1 
violent noise in the adjoining 
l field. h 
Sharp and good, but low. 
6 
La Canche 
10 16 25*2 
Feeble and high, to the right of 
the former. 
f Certainly -o, but the second un- 
1 certain, from a violent noise 
Wrotham 
IO 21 22*0 
1 which drowned the beat of 
L the watch. 
La Canche 
10 26 22-5 
10 31 25-9 
fNoise continued, and the ob- 
7 
W rotham 
< servations uncertain on ac- 
l count of it. 
8 
La Canche 
10 36 25-3 
Single explosion; well observed. 
Wrotham 
10 41 23-3 
Well observed. 
9 
La Canche 
10 46 25-4 
Single explosion; extremely f. 
10 
Wrotham 
La Canche 
Wrotham 
10 51 23-4 
10 56 21-5 
Well observed. 
The train seen. No explosion. 
The signal not repeated. 
Sixth Day, July 16, 1825. 
No. 
h. m. s. 
Remarks. 
La Canche 
9 26 26’3 
Extremely faint. 
I 
Wrotham 
9 3 1 3 l ‘ 4 r 
The decimal correct, the second 
possibly erroneous from noise. 
2 
La Canche 
9 3 6 J 9 ' 1 
2 4‘3 
Small bright spark. 
Broad feeble flash, higher, and to 
the apparent right 
Wrotham 
9 4 1 3 °'° 
Exact on the beat. 
La Canche 
9 4 6 3 8- ° 
Single bright flash. 
3 
Wrotham 
La Canche 
9 51 26-1 
Explosion distinct but unex- 
pected, as it happened before 
the rocket reached its greatest 
elevation. 
4 
Wrotham 
La Canche 
10 1 31*6 
Regular, and well observed. 
5 
Wrotham 
00 
b 
0 
Regular, and well observed. 
6 
La Canche 
Wrotham 
10 16 32-2 
10 21 327 
Bright single flash. 
La Canche 
10 26 217 
Excessively faint. 
7 
Wrotham 
10 31 29 1 
8 
La Canche 
Wrotham 
10 36 27*2 
10 41 35 ‘9 
Extremely faint. 
La Canche 
10 46 18-2 
Very bright. 
9 
W rotham 
10 C 1 2q q 
10 
La Canche 
10 56 29 6 
Very bright. Observed with M. 
Wrotham 
1 1 I 297 
Largeteau’s glass ; a doubt 
having arisen as to its correct 
pointing, he having seen none of 
the La Canche signals this even- 
ing. 
