Page:Notes on the State of Virginia (1802).djvu/123

Rh want of dew on the mountains. That the dew is very rare on their higher parts, I may ſay with certainty, from 12 years obſervations, having ſcarcely ever, during that time, ſeen an unequivocal proof of its exiſtence on them at all during ſummer. Severe froſts in the depth of winter prove that the region of dews extends higher in that ſeaſon than the tops of the mountains: but certainly, in the ſummer ſeaſon, the vapors, by the time they attain that height, are become ſo attenuated as not to ſubſide and form a dew when the ſun retires.

The weavil has not yet aſcended the high mountains.

A more ſatisfactory eſtimate of our climate to ſome, may perhaps be formed, by noting the plants which grow here, ſubject however to be killed by our ſevereſt colds. Theſe are the fig, pomegranate, artichoke, and European walnut. In mild winters, lettuce and endive require no ſhelter; but generally they need a ſlight covering. I do not know that the want of long moſs, reed, myrtle, ſwamp laurel, holly and cypreſs, in the upper country, proceeds from a greater degree of cold, nor that they were ever killed with any degree of cold in the lower country. The aloe lived in Williamſburgh, in the open air, through the ſevere winter of 1779, 1780.

A change in our climate, however, is taking place very ſenſibly. Both heats and colds are become much more moderate within the memory even of the middle-aged. Snows are leſs frequent and leſs deep. They do not often lie, below the mountains, more than one, two, or three days, and very rarely a week. They are remembered to have been formerly frequent, deep, and of long