Page:Notes on the State of Virginia (1853).djvu/100

84 By this it may be seen that the Southwest wind prevails equally at both places; that the Northeast is, next to this, the principal wind towards the sea coast, and the Northwest is the predominant wind at the mountains. The difference between these two winds to sensation, and in fact, is very great. The Northeast is loaded with vapor, insomuch that the salt-makers have found that their crystals would not shoot while that blows; it brings a distressing chill, is heavy and oppressive to the spirits; the Northwest is dry, cooling, elastic and animating. The Eastern and Southeastern breezes come on generally in the afternoon. They have advanced into the country very sensibly within the memory of people now living. They formerly did not penetrate far above Williamsburgh. They are now frequent at Richmond, and every now and then reach the mountains. They deposit most of their moisture, however, before they get that far. As the lands become more cleared, it is probable they will extend still further westward.

Going out into the open air, in the temperate, and in the warm months of the year, we often meet with bodies of warm air, which, passing by us in two or three seconds, do not afford time to the most sensible thermometer to seize their temperature. Judging from my feelings only, I think they approach the ordinary heat of the human body. Some of them perhaps go a little beyond it. They are of about 20 or 30 feet diameter horizontally. Of their height we have no experience; but probably they are globular volumes wafted or rolled along with the wind. But whence taken, where found, or how generated? They are not to be ascribed to volcanoes, because we have none. They do not happen in the Winter when the farmers kindle large fires in clearing up their grounds. They are not confined to the Spring season, when we have fires which traverse whole counties, consuming the leaves which have fallen from the trees. And they are too frequent and general to be ascribed to accidental fires. I am persuaded their cause must be sought for in the atmosphere itself, to aid us in which I know but of these constant circumstances: a dry air, a temperature as warm at least as that of the Spring or