CHAP. 42. (42.)—OR UNCERTAIN STATES OF THE WEATHER.

But I would not deny, that there may exist showers and winds, independent of these causes, since it is certain that an exhalation proceeds from the earth, which is sometimes moist, and at other times, in consequence of the vapours, like dense smoke; and also, that clouds are formed, either from the fluid rising up on high, or from the air being compressed into a fluid[1]. Their density and their substance is very clearly proved from their intercepting the sun's rays, which are visible by divers, even in the deepest waters[2].

1. The doctrine of Aristotle on the nature and formation of mists and clouds is contained in his treatises De Meteor. lib. i. cap. 9. p. 540, and De Mundo, cap. 4. p. 605. He employs the terms a)tmis\s, ne/fos, and nefe/lh, which are translated vapor, nubes and nebula, respectively. The distinction, however, between the two latter does not appear very clearly marked either in the Greek or the Latin, the two Greek words being indiscriminately applied to either of the Latin terms.

2. It is doubtful how far this statement is correct; see the remarks of Hardouin, Lem. i. 320.