GUAYMAS. 
467 
place. The climate is dry and exceedingly hot, the 
thermometer ranging during the day from 95 to 98° 
Fahrenheit, and often exceeding 100°. Notwithstand- 
ing this intense heat, the place is considered healthy, 
it being free from the epidemics which too often 
accompany such high temperatures. This may, in some 
respect, be owing to a westerly breeze, which springs 
up in the evening, as at San Francisco and other places 
on the Californian coast, and brings with it the cool air 
from the ocean. This sudden change of temperature 
doubtless arises from the intense heat on the desert 
during the day, when the air in a rarified state passes 
upwards into the higher regions. As the sun descends, 
the air rushes in from the ocean to fill up the vacuum. 
This will account for the prevalence of the south-west- 
erly winds at certain seasons throughout the country 
between the Gila and the Californian gulf, and the mois- 
ture they bring with them. The winter is moderate and 
the temperature variable, sometimes reaching 90 de- 
grees. The weather to-day, 31st December, would be 
called hot in New- York; and I noticed that even the 
inhabitants sought the shady side of the street. 
The town lies in a valley almost ten miles in 
length by four in width. It is closely hemmed in on 
the east by a mountain or rugged pile of rocks com- 
posed of crystallized carbonate of lime, of a beautiful 
texture, in which white and cream color predominate, 
relieved by dark and deep indentations. It is 
called La Sierra de la Camji^ana^ or the Bell Moun- 
tain, from the fact that the sonorous material of 
which it is composed emits a sound when struck. Se- 
veral small ranges of mountains, known as the Colorado 
