The spring opens the seas for the navigators. In the beginning of this season the west winds soften, as it were, the winter sky, the sun having now gained the 25th degree of Aquarius; this is on the sixth day before the Ides of February[361]. This agrees, for the most part, with all the remarks that I shall subsequently make, only anticipating the period by one day in the intercalary year, and again, preserving the same order in the succeeding lustrum[362]. After the eighth day before the Calends of March[363], Favonius is called by some Chelidonias[364], from the swallows making their appearance. The wind, which blows for the space of nine days, from the seventy-first day after the winter solstice[365], is sometimes called Ornithias, from the arrival of the birds[366]. In the contrary direction to Favonius is the wind which we name Subsolanus, and this is connected with the rising of the Vergiliæ, in the 25th degree of Taurus, six days before the Ides of May[367], which is the time when south winds prevail: these are opposite to Septemtrio. The dog-star rises in the hottest time of the summer, when the sun is entering the first degree of Leo[368]; this is fifteen days before the Calends of August. The north winds, which are called Prodromi[369], precede its rising by about eight days. But in two days after its rising, the same north winds, which are named Etesiæ[370], blow more constantly during this period; the vapour from the sun, being increased twofold by the heat of this star, is supposed to render these winds more mild; nor are there any which are more regular. After these the south winds become more frequent, until the appearance of Arcturus[371], which rises eleven days before the autumnal equinox. At this time Corus sets in; Corus is an autumnal wind, and is in the opposite direction to Vulturnus. After this, and generally for forty-four days after the equinox, at the setting of the Vergiliæ, the winter commences, which usually happens on the third of the Ides of November[372]. This is the period of the winter north wind, which is very unlike the summer north wind, and which is in the opposite direction to Africus. For seven days before the winter solstice, and for the same length of time after it, the sea becomes calm, in order that the king-fishers may rear their young; from this circumstance they have obtained the name of the halcyon days[373]; the rest of the season is winterly[374]. Yet the severity of the storms does not entirely close up the sea. In former times, pirates were compelled, by the fear of death, to rush into death, and to brave the winter ocean; now we are driven to it by avarice[375]. CHAP. 48.—NATURE OF THE WINDS[376].