FV. Hayden on the Geology, &c. 245 
air ladened with moisture from the Pacific ascend the western 
Slope of the mountains, become condensed and deposit their bur- 
dens for the most part before reaching the eastern slope 
rent, sweeping over the Pacific Ocean, and consequently charged 
with moisture, will impinge on the Coast range of mountains of 
Oregon and California, and, in ascending its slopes, deposit mois- 
ture on the western declivity, giving fertility and a healthful 
climate to a narrow strip of country bordering on the ocean, and 
Sterility to the eastern slope. All the moisture however 
Rot be deposited in the passage over the first range, but a por- 
tion will be precipitated on the western side of the next, until 
it reaches the eastern elevated ridge of the Rocky Mountain sys: 
‘em, when, we think, it will be nearly if not quite exhausted. 
We are how supposing that the climatic conditions, winds, cur- 
the present day. We therefore venture the suggestion that up 
th ie rtiary deposits 
‘ * Lindley’s Vegetable Kingdom, p. 136. 
_ Washington, D. C., January 20, 1861. 
AM. Jour. Sc.—Secoxp Series, VoL. XXXI, No. 92.—Marcu, 1861. 
32 
