1909-10.] Halley’s Comet and the Earth’s Atmosphere. 
547 
Table II. — continued . 
Date. 
Hour. 
Number 
of 
Particles. 
Wind 
Direction 
and Force. 
Tempera- 
ture. 
Wet-Bulb 
Depression. 
Cloud 
Amount. 
Trans- 
parency 
of Air. 
10 
8.45 
3175 
N.E. *5 
60 
8 
0 
Medium 40 
55 
10 
3400 
N.E. 1 
66 
10 
55 
55 
55 
1 
2300 
N.E. *5 
74 
16 
55 
55 
55 
7 
3400 
W.S.W. -5 
67 
8 
55 
55 
55 
9.30 
2700 
N.E. 2 
60-5 
6 
55 
11 
8.45 
2100 
Calm 
58-5 
6 
55 
Thick 
55 
10.30 
3600 
W. -2 
60 
4 
55 
„ 15 
55 
11 
3580 
W. -5 
60-5 
4 
55 
55 
Table III. — Showing the Mean Limit of Visibility of the Air in Miles at Falkirk 
for Winds from Different Directions, and for each increase of 2° in the 
Wet-Bulb Depression, from 1891 to 1896. 
Direction 
of 
Wind. 
2 C 
3° and 4°. 
5° and 6°. 
7° and 
over. 
Number 
Limit 
Number 
Limit 
Number 
Limit 
N umber 
Limit 
of Obser- 
of Visi- 
of Obser- 
of Visi- 
of Obser- 
of Visi- 
of Obser- 
of Visi- 
vations. 
bility. 
vations. 
bility. 
vations. 
bility. 
vations. 
bility. 
N. 
1 
80 
5 
189 
7 
182 
N.N.E. 
3 
47 
2 
37 
N.E. 
3 
32 
5 
33 
3 
33 
4 
54 
E.N.E. 
6 
6 
7 
21 
3 
16 
6 
19 
E. 
5 
8 
14 
12 
15 
19 
20 
19-5 
E.S.E. 
S.E. 
3 
14 
*2 
22 
1 
15 
S.S.E. 
3 
12 
1 
12 
2 
15 
S. 
4 
*8 
8 
15 
8 
20 
6 
25 
S.S.W. 
5 
6 
12 
12 
7 
13 
3 
38 
s.w. 
10 
6 
26 
13 
19 
13 
14 
19 
W.S.W. 
3 
14 
8 
’ 22 
13 
31 
13 
42 
w. 
6 
50 
21 
110 
23 
110 
8 
156 
W.N.W. 
2 
75 
3 
190 
8 
188 
N.W. 
4 
142 
10 
195 
7 
200 
N.N.W. 
2 
175 
