Natural Questions Chapter 11

Nunc (quod promisi) dicendum est quare etesiae nos non adiuuent nec quicquam huic conferant causae. Diximus ante lucem auram incitari, eandem subsidere, cum illam sol attigit. Atqui etesiae ob hoc somniculosi a nautis et delicati uocantur quod, ut ait Gallio, "mane nesciunt surgere": eo tempore fere incipiunt prodire quo ne pertinax quidem aura est. Quod non accideret, si ut auram ita illos comminueret sol. Adice nunc quod, si causa illis flatus esset spatium diei ac longitudo, et ante solstitium flarent, cum longissimi dies sunt et cum maxime niues tabescunt; Iulio enim mense iam despoliata sunt omnia aut certe admodum pauca iacent adhuc sub niue.

Maintenant, comme je l’ai promis, expliquons pourquoi ces vents ne sont d’aucun secours et ne fournissent aucune preuve à la cause que je combats. Nous disons que l’aurore éveille le souffle du vent, qui baisse sitôt que l’air a été touché du soleil : or, les gens de mer nomment les étésiens dormeurs et paresseux, attendu, comme dit Gallion, qu’ils ne sauraient se lever matin ; ils ne font acte de présence qu’à l’heure où les vents les plus opiniâtres ont cessé, ce qui n’arriverait pas si le soleil les paralysait comme les autres. Ajoute que, s’ils avaient pour cause la longueur du jour et sa durée, ils souffleraient avant le solstice, temps où les jours sont le plus longs et la fonte des neiges le plus active ; car, au mois de juillet, la terre est tout à fait découverte, ou du moins fort peu d’endroits sont encore cachés sous la neige.

I must now, as I promised, tell you why the Etesian winds do not give any assistance to their advocates nor contribute aught to their argument. We have said that the breeze is stirred by the morning light, but it no less surely subsides when the full sun has touched it. And yet the Etesians are called by sailors sleepy-headed and dainty, for the very reason that, as my brother Gallio puts it, they cannot get up in the morning. They begin to show face at the time when even the most persistent morning breeze has fallen. This would not occur if the sun reduced the force of the Etesians as he does that of the morning breezes. Add also that, if the cause of their rise was the lengthened space of the day, they would blow even prior to the solstice when the days are at their longest, and when the thaw of the snow is at its height. By the month of July everything is clear of snow, or, at any rate, very few places are still covered with it.