vens are rapidly carried about to the right[1]. And although, by the stars constantly revolving with immense velocity, they are raised up, and hurried on to the part where they set, yet they are all forced, by a motion of their own, in an opposite direction[2]; and this is so ordered, lest the air, being always moved in the same direction, by the constant whirling of the heavens, should accumulate into one mass, whereas now it is divided and separated and beaten into small pieces, by the opposite motion of the different stars. Saturn is a star of a cold and rigid nature, while the orbit of Jupiter is much lower, and is carried round in twelve years.[3] The next star, Mars, which some persons call Hercules[4], is of a fiery and burning nature, and from its nearness to the sun is carried round in little less than two years[5]. In consequence of the excessive heat of this star and the rigidity of Saturn, Jupiter, which is interposed between the two, is tempered by both of them, and is thus rendered salutary. The path of the Sun consists of 360 degrees; but, in order that the shadow may return to the same point of the dial[6], we are obliged to add, in each year, five days and the fourth part of a day. On this account an intercalary day is given to every fifth year[7], that the period of the seasons may agree with that of the Sun.
3 For the exact period, according to Somerville and Herschel, see note 3, p. 27.
4 Aristotle informs us, that Mars was also called Hercules or Pyrosis; De Mundo, cap. ii. p. 602. See also Apuleius, De Mundo, $ 710. Hyginus is said by Hardouin to give the name of Hercules to the planet Mars, but this appears to be an inaccuracy; he describes the planet under its ordinary appellation; lib. ii. p. 62; and ii. 78, 9.
5 Cicero, speaking of the period of Mars, says, "Quatuor et viginti mensibus, sex, ut opinor, diebus minus;" De Nat. Deor. For the exact period, see note 3, p. 27.
- ↑ Our author supposes, that the spectator has his face directed towards the south, as is the case with the modern observers. We are, however, informed by Hardouin, that this was not the uniform practice among the ancients; see the remarks of Alexandre in Lemaire, ii. 242, and of Marcus in Ajasson, ii. 269.
- ↑ The constant revolution refers to the apparent daily motion; the opposite direction to their annual course through the zodiac. Ptolemy gives an account of this double motion in his Magna Constructio, i. 7.
- ↑ 3
- ↑ 4
- ↑ 5
- ↑ "Sed ut observatio umbrarum ejus redeat ad notas." According to the interpretation of Hardouin, "Ad easdem lineas in solari horologio." Lemaire, ii. 243.
- ↑ This is an example of the mode of computation which we meet with
