The nights are cold, and affect the vegetation so far, that Indian corn will not ripen. Fruit-trees blossom early in April {291} at Nisqually and Vancouver; and at the former place, on the 12th of May, peas were a foot high, strawberries in full blossom, and salad had already gone to seed.
The mean height of the barometer, during our stay at Nisqually, was 30.046 inches, and of the thermometer 66° 58′ Fahrenheit. The thermometer at 4 A. M. on the 4th of July, was at 50° Fahrenheit, and on the same day, at 2 P. M., 90° Fahrenheit. The lowest degree was 39° at 4 A. M., May 22d, and at 5 P. M. of the same day, the temperature was 72° of Fahrenheit.
From June to September at Vancouver the mean height of the barometer was 30.32 inches, and the thermometer 66° 33′ of Fahrenheit. Out of one hundred and six days, seventy-six were fair, nineteen cloudy, and eleven rainy. The rains are light; this is evident from the hills not being washed, and having a sward to their tops, although of great declivity.
The second, or middle section, is subject to droughts. During the summer the atmosphere is much drier and warmer, and the winter much colder than in the western section. Its extremes of heat and cold are more frequent and greater, the mercury at times falling as low as minus 18° of {292} Fahrenheit in the winter, and rising to 180° [sic] in the shade in summer; the daily difference of temperature is about 40° Fahrenheit. It has, however, been found extremely salubrious, possessing a pure and healthy air.
The stations of the missionaries and posts of the Hudson’s Bay Company, have afforded me the means of obtaining information relative to the climate. Although full data have not been kept, yet these observations afford a tolerably good knowledge of the weather.
In summer the atmosphere is cooled by the strong westerly breezes, which replace the vacuum produced by the heated prairie grounds. No dews fall in this section.
The climate of the third, or eastern section, is extremely variable. The temperature during the day, differing from 50° to 60°, renders it unfit for agriculture, and there are but few places in its northern part where the climate would not effectually put a stop to its ever becoming settled.
In each day, from the best accounts, all the changes are experienced incident to spring, summer, autumn, and winter. There are places where small farms might be located, but they are few in number.
{293} Soil.—That of the first, or western section varies in the northern parts from a light brown loam to a thin vegetable earth, with gravel and sand as a sub-soil: in the middle parts, from a rich heavy loam and unctuous clay to a deep heavy black loam on a trap rock; and in the southern, the soil is generally good, varying from a black vegetable loam to decomposed basalt, with stiff clay, and portions of loose gravel soil. The hills are generally basalt, and stone, and slate.