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Barometer and Temperature Indications.—The following are noted by P. R. Jameson. They apply chiefly to that part of the United States and Canada east of the Rocky Mountains, approximately from the latitude of the Ohio River to that of the Saskatchewan River.

Humidity Indications.—The gathering moisture of the air or, technically, its increasing humidity, is an indication of unsettled weather. Ordinarily, the air which may be at the dewpoint at daylight becomes relatively dry at midday because its higher temperature gives it what is popularly termed “a greater capacity for moisture.” But if the relative humidity remains high in the middle of the day it is evident that the absolute humidity has increased, and unsettled weather may be expected.