I
PLAGUE AND ATMOSPHERIC HUMIDITY.— April, 1903.
DATE. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
100
98
96
94
92
90
RELATIVE HUMIDITY OF ATMOSPHERE PER CENT
70
72
* * * * * co
76
74
88
86
84
82
80
78
68
66
64
62
60
58
56
54
52
50
48
46
44
42
40
50
48
46
44
42
40
38
36
34
32
30
28
26
24
22
20
18
16
14
12
10
8
6
4
2
0
PLAGUE CASES PER DAY
DATE.1 2 3 4 5 6 7
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