20 
MR. RUMKER’S OBSERVATIONS 
Remarks on the preceding Eclipse. 
Before the end of the eclipse I distinctly saw, on that part of 
the sun from which the moon parted, this appearance, which 
could have only arisen from projecting points on the moon’s 
surface. 
The vanishing of the last black spot A was equal to the im- 
mersion of a fixed star. 
Owing to the oblique direction in which the moon traversed 
the sun, the diminution of the shade was very slow, so that this 
eclipse is not well qualified for deducing the geographic longitude, which would 
be greatly influenced by any small error of the moon’s tables in latitude, or an 
erroneous assumption of the ratio of the earth’s axes. Whereas, on the con- 
trary, this ratio might with considerable accuracy be deduced from the pre- 
ceding micrometrical measurements, if compared with any corresponding 
observations made in any part of Asia. 
I take this opportunity of recording the transit of Mercury over the sun’s 
disk, as observed by me the 5th November, 1822. 
b m s h m s 
Immersion of ^ ’s first limb 13 59 27.0 Emersion of first limb 16 44 23 Sid. Time. 
Complete Immersion 14 2 8 Complete Emersion . . 16 47 22 
The sun’s centre passed over the meridian at 14 38 39.41 
Mercury culminated 14 38 29.9 
The declination of £ observed with the mural circle whilst the planet passed 
upon the sun’s disk over the meridian was, 
15 43 49.24 
Refraction .... — 17.80 
15 43 31.44 
Parallax is not applied. 
I subjoin the micrometrical observations ; first in right ascension, or the 
passages over the middle wire of the micrometer of the sun’s limb and centre 
of $ in sidereal time. 
Sun 
’g 1st Limb. 
Mercury. 
Sun’ 
s 2d L. 
Sun’ 
s 1st Limb. 
Mercury. 
Sun’s 2d L. 
Sun’ 
s 1 st Limb. 
Mercury. Sun 
s 2d L. 
h 
m 
S 
m 
S 
m 
s 
h 
m 
s 
m 
S 
m 
S 
h 
m 
S 
m 
s 
m 
8 
14 
2 
4.65 
3 
58 
5 
2.5 
14 
27 
40 
28 
42.5 
29 
55.5 
15 
8 
30.7 
9 
18.2 
10 
46.2 
>> 
5 
56.5 
7 
7 
8 
12.5 
>> 
44 
2.7 
44 
58.5 
46 
27.7 
>> 
11 
50.2 
12 
37.7 
. . 
• . • . 
n 
8 
46.5 
9 
56 
11 
2.0 
>> 
47 
10 
48 
5.0 
49 
26.0 
15 
13.7 
15 
59.2 
17 
30.2 
n 
11 
43.5 
12 
52 
13 
59.5 
>> 
49 
55 
50 
50 
52 
11 
18 
12.7 
18 
56.7 
14 
51.2 
15 
58.5 
17 
6.5 
55 
4.3 
50 
57 
57 
19.7 
21 
59-9 
22 
42.7 
>> 
17 
45 
18 
51 
20 
0.5 
>> 
37 
58.7 
58 
50.7 
0 
14.7 
>> 
24 
18.2 
25 
0.7 
>> 
22 
39-7 
23 
46 
15 
0 
57.2 
1 
48.2 
3 
12.7 
r> 
26 
42.4 
28 
23.9 
. , 
, , , . 
>* 
24 
31 
25 
35 
26 
46.5 
5 
25.7 
6 
14.7 
7 
41.2 
