An essay on dew and several appearances connected with it / by William Charles Wells.

  • William Charles Wells
Date:
1815
Catalogue details

Licence: Public Domain Mark

Credit: An essay on dew and several appearances connected with it / by William Charles Wells. Source: Wellcome Collection.

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    and westerly winds, than during those, which blow from the north and the east. Aristotle* says, that Pontus is the only country, in which dew is more copious during a northerly, than during a southerly wind. But a similar fact occurs in Egypt; for _ dew is scarcely ever observed there, except while the Etesian winds prevail. Both cases, however, though contrary to the letter, are consonant with the spirit of the rule; since the north wind, in one country, proceeds from the Euxine sea, and, in the other, from the Mediterranean. Another circum- — stance, of the same kind with the blowing of wind from the south and the west, as shewing that the air contains much moisture, is the lessening of the weight of the atmosphere. My experience on this point has not, indeed, been great, as the falling of the mercury in the barometer is very commonly attended with wind or clouds, both unfavourable to the production of dew; but still the greatest dew, I have ever witnessed, occurred while the barometer was sinking. A corresponding obser- vation is made by Mr. de Luc, who says, that rain may be foretold, when dew is uncommonly abun- dant, in relation to the climate and season.+ To the greater or less quantity of moisture in the atmosphere, at the time of the action of the im- * Meteor. Lib. 1. c. x. + Rech. sur les Mod, de l’Atm. § 725. | B
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