a 
4 
4 
f 
i 
B. Silliman on the Mining Districts of Arizona. 291 
nearly 8000 feet, and thence in 18 miles farther, at ‘Rock 
Springs,’ it reaches an elevation of nearly 3800 feet above Soda 
Pe From this Psi it ef descends again in 23 miles 
owing table of monthly averages, prepared by me from 
Stark’s observations, for the three daily phony of ober yaaa 
is of interest in this connection. 
Table showing the mean monthly temperatures for one year, and aoe the 
ima and minima at Fort Mojave, Arizona, very near Lat 
anes M EANS. | | MAXIMA. MINIMA. _ 
= 7 a.m. | 2P. P. M. 7 a.m Q2pMm!19pm |7a.mM. | 2PM.) 9PM. 
November, 48 96 | 7250 | 58°76 63 85 m6 38 b4 46 
> . i 
202 | 65 396 || 57 "7 | 62 | 86 58 | 49 
. , | 40-07] 685s | 5ss8 || 62 | so | vo | 31 | 56 | 48 
ebruary, | 5231 | 78-48 | 63-06 || 6 90 | 77 | 98 | 56 | 48 
M: 2-12 | 80-00 | 64°35 |} 5 90 | 75 | 41 | 70 |: 87 
pril, 69 838 IL | 8001 83 | 102 87 52 43 60 
J Ys 73°64 | 89°29 | 78-64 102 92 62 70 
Teh 77-40 | 99:10 | 87:10 88 | 106 98 63 88 42 
uly, 423 /106-09 | 96-38 ‘11 ‘1102 | 7s) 100 1) 
ugust, 87 10667 | 97-48 95 }| 11 104 "9 9 87 
id ember, 7630 [10080 | 88:03 || 88 | 108 65 | 90 | 72 
tober, | 62:09 | 86-22 | 7229 ' 44 | 100 | 88 | 45 | 70 | 59 
From this table December is seen to be the month of lowest 
mean temperature, Febreacy the minimum degrees of heat are 
Seen in January and Febru 
The greatest neg are foutid in July and August, when the 
temperature is seen to be most remarkably uniform, the maxi- 
mum eae in fa oe aie identical for the — daily ae 
i t 
o rain of any consequence. ays 8 Stark, “ falls at this except ding 
the mow f Jul rains are of t oceurrence 
in the of July and August, though heavy ra very | nee 
ne meyeuniing hills. ae seg guage has n been regulasly. nee ay pu 
ba Lestimate the mean rain for pee ars of obser be se & 
“At Fort Yuma, near the mouth of ie tin. O Croco, accurate 
ee v been here, 
“The SaeA Seay eviertarm. Ta view of this 
