16 
A GAZETTEER OF UTAH. 
[BULL. 166. 
CLIMATE. 
A region presenting a great range of relief, like this State, naturally 
shows a wide range in climatic conditions. Accordingly, the mean 
annual temperature ranges from 65° in the valley of the Virgin, in the 
southwestern corner of the State, down to the freezing point on 
the summits of its highest peaks. In the valley of Great Salt Lake 
the mean annual temperature ranges from 50 to 55°, as it does upon 
the lower plateaus of the Colorado and its tributaries. The Uinta 
Valle} 7 , at the south base of the Uinta Range, has a mean annual tem- 
perature somewhat lower, ranging from 15 to 50°. In general, it may 
be said that the habitable regions west of the Wasatch are much 
warmer than those upon the Colorado east of that range. As this is 
for the most part an arid region, the extremes of temperature as 
between summer and winter, day and night, are great, and the relative 
humidity of the atmosphere is low. 
The rainfall also is subject to wide variation within the area of the 
State. In most of that portion which is included within the Great 
Basin less than 10 inches of rain falls annually, and similar arid con- 
ditions prevail upon the lower plateaus drained by Colorado River. 
The west base of the Wasatch Range and the valleys within the broken 
plateau country which succeed it to the southward, together with the 
Uinta Valley, receive a larger amount of precipitation, ranging in the 
course of a year from 10 to 20 inches, while upon the Wasatch and 
Uinta ranges the rainfall is much greater, probably exceeding 30 
inches annually. 
The magnetic declination throughout the State is east, and ranges 
from 11° in the southeastern corner to nearly 18° in the northwest, 
the declination increasing quite regularly from southeast to northwest. 
POPULATION. 
The population of Utah at each census since its first settlement — that 
is, 1850 — is given in the following table, with the rates of increase 
from census to census: 
Population of Utah at the census years since 1850. 
Year. 
Population. 
Per cent of 
increase. 
1850 
11,380 
40, 273 
86, 786 
143, 963 
207, 905 
247, 324 
1860 
254 
116 
66 
45 
19 
1870 
1880 
1890 
1895 
