1889 - 90 .] 
Mr J ohn Aitken on Dust Particles. 
247 
Table of the Number of Dust Particles in the Atmosphere. 
Place. 
Date. 
Hour. 
Number 
of Par- 
ticles 
per c.c. 
Wind. 
Tern pera- 
ture. 
Humidity. 
State of 
the Air. 
Remarks. 
Hyferes, . . 
Mar. 
19 
10.0 a.m. 
46,000 
S.E. 1 
11 
Clear. 
At window of hotel. 
Finouillet, . 
21 
3.30 a.m. 
5,000 
W. 1 
10 
Near top of mountain. 
Hyferes, . . 
22 
11.0 a.m. 
9,000 
W. 1 
11 
At window of the hotel. 
,, 
,, 
5,600 
,, 
Near the top of the mountain. 
Finouillet, . 
23 
3.15 p.m. 
4,100 
19,000 
S.W. 1 
9 
Thickish. 
,, 
3.45 p.m. 
Very thick. 
, , beginning to rain. 
At top of mountain. 
25 
4.0 p.m. 
12.0” 
3,550 
10,000 
W. 1 
13* 
Clear. 
La Plage, . 
,, 
Number very variabie. 
29 
2,150 
S.E. 1 
13* 
Taken on the beach. 
1.30 p.m. 
4,800 
1,850 
S.E. 0-5 
,, 
Wind fallen. 
1‘45 p.m. 
,, 
,, 
At 100 yards from shore. 
2.0 p.m. 
1,800 
,, 
)( 
At 250 ,, ,, 
Finouillet, . 
Apr. 
3 
3.30 p.m. 
4,400 
N.W. 6 
61-2 
13 
Extly. clear. 
Observed on top of mountain. 
4,500 
25,600 
W.’ 3 
,, 
,, 
Clear. 
,, ii 
4 
55 
8-5 
Wind direct from Toulon. 
Observed on the top of La 
Cannes, . . 
10 
11.0a.m. 
24,400 
1,550 
1,600 
” 
65'5 
13’ 
Veiy cleai\ 
11.30 a.m. 
,, 
Croix des Gardes. 
11 
1,950 
S.W. 3 
54 
2 
Very thick. 
ii ii 
12 
10.30 a.m. 
140.000 
150.000 
E. 1 
63 
10 
Very clear. 
Large number due to wind blow- 
,, 
t , 
135,000 
10,000 
S. 0-5 
58 
,, 
Thickish. 
ing from the town. 
13 
11.30 a.m. 
7 
On pier in west bay. 
11 
12,000 
62 
,, 
Very clear. 
On shore in west bay. 
Mentone, . . 
25 
3.0 p.m. 
1,200 
N.W. 1 
12 
Observed on hill about 1000 feet 
,, 
7,200 
S.E. 1 
13 
high to the N.W. of Mentone. 
27 
10.0 a.m. 
5,000 
S.E. 0-5 
64 
Observed in small boat outside 
BeUagio, . . 
May 
3 
11.15 a.m. 
10,000 
S.W. 0-5 
64 
7 
Thickish. 
the pier. 
Observed at open window. 
3.0 p.m. 
10,000 
S. 0-5 
63 
6 
,, 
Observed on the top of the Villa 
3.30 p.m. 
9,500 
,, 
Serbelloni. 
6 
3.0 p.m. 
3,000 
S.W.’ 0-2 
60 
3 
Thick. 
At open window, rain. 
7 
2.30 p.m. 
5,600 
S. 0-2 
66-5 
7-5 
Thick. 
Taken at window. 
■ 
8 
12.30 p.m. 
2,900 
S.W. 1 
62 
5 
Very thick. 
,, ,, been rain. 
Taken at window. 
Baveno, . . 
13 
10.30 a.m. 
9,000 
N.W. 0-2 
70 
10 
Thick. 
3.30 p.m. 
6,780 
Very thick. 
ii ii 
14 
11.0 a.m. 
3,200 
N.W. 3 
56*5 
3**5 
,, „ wet night, rain- 
ing, distant thunder. 
At window, still raining. 
3.0 p.m. 
3,800 
N.W. 4 
57 
4 
Thickish. 
15 
10.30 a.m. 
10,000 
Calm 
58 
2 
,, ,, raining, calm. 
12.15 p.m. 
6,120 
V ,, ,, 
2.0 p.m. 
4,500 
e.’ot 
59* 
2* 
Extly. "thick. 
ii >> ii 
3.0 p.m. 
2,900 
E. 0-2 
Very thick. 
j> ii ii 
Simplon Pass, 
16 
10.0 a.m. 
5,600 
N.W. 3 
58* 
3*5 
Very thick. 
,, „ wet morning. 
3.30 p.m. 
850 
N.W. 0-5 
Clear. 
Taken a short way up the 
3.45 p.m. 
546 
Simplon Pass. 
Increase due to change of wind. 
1 
4.0 p.m. 
14,000 
s.e!’o-5 
,, 
Baveno, . . 
Locarno, . . 
17 
10.0 a.m. 
6,250 
S.E. 0-5 
65* 
6* 
Medium. 
Taken at window. 
11.15 a.m. 
6,600 
,, 
Thickish. 
Taken on hill side at 600 feet 
18 
4.0 p.m. 
1,150 
£*2 
6* 
Rigi Kulm, . 
21 
2.0 p.m. 
1,300 
Variable 
46 
1-5 
Thick fog. 
above the lake. 
Taken on the top of the hill. 
3.30 p.m. 
285 
11 11 
4.30 p.m. 
210 
45 
1 *5 
11 11 
11 
227 
,, 
11 
22 
9.30 a.m. 
850 
S.E. 2 
51 
6* 
Clear. 
1 1 
? 
700 
11.30 a.m. 
434 
11 11 
518 
Occasional passing fog. 
3.30 p.m. 
1,450 
55* 
4* 
Haze. 
1 1 
1 1 
1,550 
Thunder storm to the east. 
11 
1,550 
2,050 
11 
ii 
11 
ii ii 
11 
1 1 
2,200 
1111 
11 
4.30 p.m. 
2,350 
11 
” 
2,050 
50* 
4* 
11 11 
