Physical Science in the Time of Nero: Naturales Quaestiones (1910) - Page 21

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III.	But wind does not depend solely on density; cloudy or misty weather does not necessarily produce wind, whereas wind is produced when the morning sun dissipates the air. Democritus is, therefore, wrong . . . . . . . . .	195
IV.	Wind arises in two ways: from the interior of the earth by emission—like gas on the stomach!—and from evaporation . .	196
V.	The air has an inherent power of movement, which is the primary cause of wind, evaporation being a less powerful one. Water has the power of moving and imparting life to animals and plants .	197
VI.	Even fire, the destroyer, sometimes generates life. Air, in the same way, has a unique power of its own . . . . .	197
VII.	Breezes before dawn arise from rivers, etc. They do not last long .	198
VIII.	The "gulf" wind (egkolpias original: "ἐγκολπίας"): its origin and duration . . .	198
IX.	The connection of winds with the seasons of the year and with the heat and light of the sun. The sun does not directly cause the winds .	200
X.	Some cite the Etesian winds as proof that the sun does cause them. They blow in summer when the snows melt and moisture is carried south .	201
XI.	But as to the effect of the sun, there is no similarity between the Etesian winds, which do not rise until late in the day, and winds that rise at dawn and fall as the day advances . .	202
XII.	Cloud squalls (eknephias original: "ἐκνεφίας"). Their formation and combinations .	203
XIII.	The breaking up of clouds produces wind. Air, in an effort to get free, or heat, may cause this. An interruption of free passage may produce a whirlwind, just as an obstacle in a river creates a whirlpool. Violent whirlwinds can catch fire (prester original: "πρηστήρ"). Some winds produce different ones. An analogy holds between air and drops of moisture. A union of forces in air or in dew is necessary to provide impulse and produce a current. Air and wind are merely a matter of degree . . . . . . . . . . .	204
XIV.	The mode in which subterranean winds are generated and make their escape . . . . . . . . . . .	205
XV.	The ancient miners of Philip's saw rivers and vast underground reservoirs. It is some consolation to read such a story, which shows that greed is no new vice: older generations were as reckless as we are in their search for treasure that is better left hidden . . .	207
XVI.	The four cardinal winds. The full list includes twelve. Their names and directions . . . . . . . . .	208
XVII.	The great circles of the earth that provide twelve divisions, and therefore prescribe the possible number of the winds . . .	210
XVIII.	The uses of wind and the illustration provided of the wisdom of Providence. Crops are dependent on it, as is commerce. But we turn the sea into a highway for war rather than peace. We go seeking death, as if it were not already near. Xerxes, Alexander, and Crassus are warnings regarding the mischievous use of power to cross the sea. Perhaps it would have been better if the winds had never been given at all. But the value of a natural gift must not be judged by the depraved use of it. Man has perverted every gift, even sight and speech, in the same way . . . .	212