48 
GRAVEL AND PLACER MINING IN ALASKA. 
[BULL. 26? 
The accompanying tables, compiled by Cleveland Abbe, jr., on th 
dates of opening and closing of interior water navigation and of tern 
perature, are here inserted because they have a direct 'bearing oi 
mining operations. In general, though the fact is contrary to popu 
lar opinion, it can be stated that climatic conditions, so far as tern 
perature is concerned, form the least of the hardships with which th 
miner has to contend. It is safe to say that no more generally health; 
climate can be found in any portion of the known world. Data i 
regard to the length of season available for use of running water wi] 
be found in the tabulated list of water conduits. (See table 8, p. 104. 
Table 2. — Rainfall in Alaska. 
[Compiled by Cleveland Abbe, jr.] 
RAINFALL IN INCHES. 
Station. 
Jan. 
Feb. 
Mar. 
Apr. 
May. 
June. 
July. 
Aug. 
Sept. 
Oct. 
Nov. 
Dec. 
Year. 
Lengt 
recorc 
Juneau 
Skagway 
Fort Liscum 
Kenai 
St. Michael 
Camp Davidson. . . 
Eagle 
10.6 
.9 
9.7 
.8 
.9 
.6 
.4 
4.9 
.6 
1.0 
.7 
.2 
.9 
.6 
6. 6 
.6 
5.5 
1.0 
.5 
.2 
.4 
5.3 
2.4 
4.5 
.8 
.4 
.6 
.8 
7.4 
.8 
2.3 
1.0 
1.3 
.6 
.8 
5.0 
.6 
.7 
.7 
1.5 
1.4 
.5 
.3 
5.6 
1.7 
4.2 
1.7 
2.5 
1.7 
2.2 
2.0 
7.5 
1.5 
12.4 
3.3 
3.3 
3.0 
2. 
2.7 
12.2 
3.5 
14.2 
2.5 
4.0 
2.4 
1.1 
10.1 
3.2 
14.3 
2.1 
1.7 
.2 
.8 
10. 5 
2.2 
6.6 
1.1 
1.2 
.7 
.6 
8.2 
3.8 
6.0 
.9 
.8 
.3 
.5 
93.1 
21.8 
81.3 
16.6 
18.1 
[13.4] 
11.4 
Yr. m 
13 

2 
5 
7 










Camp Colonna 
Fort Adams 
Fort Gibbon 
.7 
1.7 
2.1 
.9 
.8 
.7 
.1 
.4 
.6 
1.5 
.4 
2.3 
.1 
1.2 
1.4 
1.5 
.45 
1.2 
.8 
1.4 
1.4 
.2 
.65 
> 6.1 
>15.5 
> 7.5 
>11.7 
> 5.3 
2.2 
1.5 
2.5 
1.6 
1.4 
1.2 
2.0 
1.25 
.7 
1.8 
.9 
.4 
1.5 
1.4 
>.2 
.5 
.4 
.6 
2.8 
1.1 
2.0 
. 7 
Dawson, Y. T. «... 
.7 
.4 
.2 
.78 
.58 
1.71 
aAuthority: Inspector of Fisheries, Yukon Territory. 
NUMBER OF RAINY DAYS. 
Station. 
Jan. 
Feb. 
Mar. 
Apr. 
May. 
June. 
July. 
Aug. 
Sept. 
Oct. 
Nov. 
Dec. 
Yea: 
Juneau 
18.1 
7.5 
17.5 
5.3 
8.1 
16.0 
6.2 
11.2 
2.5 
5.0 
4.4 
5.5 
14.0 
5.8 
18.7 
3.0 
14.5 
7.4 
7.4 
6.0 
4.8 
15.0 
10.5 
9.0 
6.4 
7.8 
9.0 
8.6 
16.7 
4.7 
9.0 
6.4 
9.1 
7.0 
6.5 
14.6 
5.0 
8.0 
5.1 
10.4 
11.0 
9.5 
4.0 
5.0 
15.5 
5.7 
14.5 
8.9 
13.6 
14.0 
13.0 
8.5 
15.6 
8.5 
28.5 
13.4 
16.7 
16.0 
13.0 
9.0 
18.4 
13.5 
22.5 
11.7 
18.5 
16.0 
9.8 
19.8 
12.0 
22.0 
10.0 
11.4 
6.0 
7.8 
18.4 
8.0 
11.5 
7.4 
11.4 
13.0 
7.0 
19.8 
11.7 
13.0 
6.0 
6.9 
7.0 
5.7 
20] 
91 
171 
91 
121 
[151. 
9' 
Fort Liscum 
Kenai 
St. Michael 
Camp Davidson . . 
Eagle 
Circle 
Camp Colonna . . . 
14.0 
11.0 
16.0 
8.6 
12.0 
13.0 
4.0 
3.5 
4.0 
12.0 
8.0 
12.5 
2.0 
6.0 
13.3 
4.0 
14.0 
10.0 
14.0 
8.0 
2.0 
> 7! 
Fort Adams 
16.0 
14.0 
16.0 
17.0 
8.0 
12.6 
8.0 
Mil 
Fort Gibbon 
>5 
>io 
Nulato 
5.0 
15.6 
7.0 
6.0 
12.5 
15.3 
>2.0 
7.6 
4.0 
7.0 
Anvik 
13.0 
12.0 
11.0 
7.0 
Copper Center 
Numbers in [ ] s 
Numbers preced 
ire tot 
ed by 
lis ma 
> are 
de up 
knowr 
from i 
l to be 
nonth 
toosu 
sin di 
lall. 
fferent 
year 
