24 Value of Dry Air. 
the effective sun rays, and so retard fruit ripening. Hence an. 
apparently sunny country which has much invisible watery vapor 
in the air, may prove defective in fruit-ripening qualities. 
It is true that air free from humidity allows rapid escape of 
heat by radiation as well as free access of it, and in dry air frost 
is more severe, but at the time of the greatest fruit growth, from 
June to October, radiation down to a frost point is prevented by 
other natural agencies. In the early spring and late autumn 
the humidity percentage rises again and checks radiation just 
at the time of the year when it is most desirable to have it 
checked. 
The following table, compiled from the records of the 
United States Weather Bureau, shows the prevailing relative 
humidity in the East and South and in California:— 
NorMAL RELATIVE HuMIDITY AT EASTERN AND CALIFORNIA POINTS, 
1888 to 1896, FROM THE RECORDS OF THE U. S. WEATHER BUREAU. 
er 
ae 
-EASTERN e 3 g a | Z 3 z [ges 
‘STATIONS. £ s Z 3 es A fe) z, : a g 
Jacksonville, Fla.| 72.3 | 73.0 | 77.6 | 78.6 | 80.9 | 82.9 | 79.8 | 82.2 | 78.3 
Philadelphia, Pa..| 63.4 | 68.9 | 69.2 | 68.6 | 71.2 | 75.2 | 70.7 | 73.6 | 70.1 
Rochester, N. Y..| 67.8 | 68.6 | 69.1 | 67.3 | 70.7 | 75.2 | 75.6 | 76.2 | 71.3 
Grand Haven, M.| 70.9 | 71.4 | 73-7 | 69-0 | 73-1 | 750 | 75.7 | 79-1 | 73-5 
St. Louis, Mo ..... 63.7 | 67.8 | 68.8 | 66.3 | 67.3 | 70.2 | 65.9 | 71.1 | 67.6 
New Orleans, La..| 76.0 | 74.2 | 78.1 | 78.3 | 78.8 | 77.3 | 74-0 | 79-4 | 78.0 
Galveston, Tex...} 84.6 | 78.0 | 79.3 | 77.4 | 78.1 | 77.2 | 75.6 | 80.4 | 78.5 
CALIFORNIA 
STATIONS. 
Los Angeles 75.2 | 73.0 | 75.4 | 76.2 | 72.9 | 74.3 | 66.6 | 73.3 
Fresno....... 52.7 | 42.4 | 34-7 | 34.7 | 43.6 | 55.1 | 64.1 | 48.3 
Sacramento 67.6 | 66.1 | 59.8 | 59.8 | 59.0 | 62.4 | 66.8 | 63.6 
Red Bluff.........../ 61.9 | 56.8 | 43.7 | 35.6 | 35.3 | 43.6 | 51.6 | 60.7 | 488 
THE THREE POINTS COMBINED. 
The three great advantages of the California climate,— 
abundant heat, continuous sunshine, and dry air,—taken in con- 
nection with the fitness of the soil and the great length of the 
growing season, insure the characteristic excellence of California 
fruit, and the early maturity, great growth, and abundant fruit- 
age of our trees and vines. Heat, sunshine, dry air, and a rain- 
less summer also minister directly to the curing of fruits in the 
open air. All things considered, it is doubtful whether any area 
of the world excels California in possession of natural adaptation 
to fruit production and preservation. 
