Page:Mathematical collections and translations, in two tomes - Salusbury (1661).djvu/338

dayes, or thereabouts, the sole annual motion of the Earth between Mars and Venus,The sole annual motion of the Earth causeth great inequality of motions in the five Planets. causeth the apparent inequalities in all the five stars before named. And for a facile and full understanding of the whole, I will describe this figure of it. Therefore suppose the Sun to be placed in the centre O, about which we will draw the Orb described by the Earth, with the annual motion BGM, and let the circle described, v. gr. by Jupiter about the Sun in 12. years, be this BGM, and in the starry sphere let us imagine the Zodiack YVS.

A demonstration of the inequalities of the three superiour Planets dependent on the annual motion of the Earth. Again, in the annual Orb of the Earth let us take certain equal arches, BC, CD, EF, FG, GH, HI, IK, KL, LM}}, and in the Sphere of Jupiter let us make certain other arches, passed in the same times in which the Earth passeth hers, which let be BC, CD, DE, EF, FG, GH, HI, IK, KL, LM, which shall each be proportionally lesse than these marked in the Earths Orb, like as the motion of Jupiter under the Zodiack is slower than the annual. Supposing now, that when the Earth is in B, Jupiter is in B, it shall appear to us in the Zodiack to be in P, describing

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