natura ibi et ferme reliquas complexa aeris1 causas, quoniam et tonitruum et fulminum iactus horum violentiae plerique adsignant, quin et ideo lapidibus pluere interim, quia vento sint rapti; et multa similiter. quam ob rem simul plura dicenda sunt.105
XXXIX. Tempestatum imbriumque2 quasdam statas esse causas, quasdam vero fortuitas aut adhuc rationis inconpertae, manifestum est. quis enim aestates et hiemes quaeque in temporibus annua vice intelleguntur siderum motu fieri dubitet? ut solis ergo natura temperando intellegitur anno, sic reliquorum quoque siderum propria est cuiusque3 vis et ad suam cuique naturam fertilis. alia sunt in liquorem soluti umoris fecunda, alia concreti in pruinas aut coacti in nives aut glaciati in grandines, alia flatus, alia teporis, alia vaporis, alia roris, alia frigoris.4 nec vero haec tanta debent existimari quanta cernuntur, cum esse eorum nullum minus 106luna tam inmensae altitudinis ratio declaret. igitur in suo quaeque motu naturam suam exercent, quod manifestum Saturni maxime transitus imbribus faciunt. nec meantium modo siderum haec vis est sed multorum etiam adhaerentium caelo, quotiens errantium accessu inpulsa aut coniectu radiorum exstimulata sunt, qualiter in suculis sentimus accidere, quas Graeci ob id pluvio nomine hyadas5
the phenomena caused by the air, as most men attribute- the hurling of thunderbolts and lightning to the winds’ violence, and indeed hold that the cause of the rain of stones that sometimes occurs is that the stones are caught up by the wind; and likewise many other things. On this account more facts have to be set out at the same time.
XXXIX. Storms and rain obviously have someRain. regular causes, but some that are accidental, or at all events not hitherto explained. For who can doubt that summer and winter and the yearly vicissitudes observed in the seasons are caused by the motion of the heavenly bodies? Therefore as the nature of the sun is understood to control the year’s seasons, so each of the other stars also has a force of its own that creates effects corresponding to its particular nature. Some are productive of moisture dissolved into liquid, others of moisture hardened into frost or coagulated into snow or frozen into hail, others of a blast of air, others of warmth or heat, others of dew, others of cold. But it must not be thought that the stars are of the size that they appear to the sight, since the consideration of their immense altitude proves that none of them is smaller than the moon. Consequently each of them exercises its own nature in its own motion, a fact which the transits of Saturn in particular make clear by their storms of rain. Nor does this powerInfluence of hearenly weather, belong to the moving stars only, but also to many of those that are fixed to the sky, whenever they are impelled forward by the approach of the planets or goaded on by the impact of their rays, as we observe occurring in the case of the Little Pigs, the Greek name for which is consequently the Hyades, a word