Lastly, It moving thus upon the Æquator, unto what position soever, although it had made a day, yet could it have made no year: for it could not have had those two motions now ascribed unto it, that is, from East to West, whereby it makes the day, and likewise from West to East, whereby the year is computed. For according to received Astronomy, the poles of the Æquator are the same with those of the _Primum Mobile_. Now it is impossible that on the same circle, having the same poles, both these motions from opposite terms should be at the same time performed; all which is salved, if we allow an obliquity in his annual motion, and conceive him to move upon the Poles of the Zodiack, distant from these of the world 23 degrees and an half. Thus may we discern the necessity of its obliquity, and how inconvenient its motion had been upon a circle parallel to the Æquator, or upon the Æquator it self. Now with what Providence this obliquity is determined, we shall perceive upon the ensuing inconveniences from any deviation. For first, if its obliquity had been less (as instead of twenty three degrees, twelve or the half thereof) the vicissitude of seasons appointed for the generation of all things, would surely have been too short; for different seasons would have hudled upon each other; and unto some it had not been much better than if it had moved on the Æquator. But had the obliquity been greater than now it is, as double, or of 40 degrees; several parts of the earth had not been able to endure the disproportionable differences of seasons, occasioned by the great recess, and distance of the Sun. For unto some habitations the Summer would have been extream hot, and the Winter extream cold; likewise the Summer temperate unto some, but excessive and in extremity unto others, as unto those who should dwell under the Tropick of Cancer, as then would do some part of _Spain_, or ten degrees beyond, as _Germany_, and some part of _England_; who would have Summers as now the _Moors_ of _Africa_. For the Sun would sometime be vertical unto them: but they would have Winters like those beyond the Artick Circle; for in that season the Sun would be removed above 80 degrees from them. Again, it would be temperate to some habitations in the Summer, but very extream in the Winter: temperate to those in two or three degrees beyond the Artick Circle, as now it is unto us; for they would be equidistant from that Tropick, even as we are from this at present. But the Winter would be extream, the Sun being removed above an hundred degrees, and so consequently would not be visible in their Horizon, no position of sphere discovering any star distant above 90 degrees, which is the distance of every Zenith from the Horizon. And thus if the obliquity of this Circle had been less, the vicissitude of seasons had been so small as not to be distinguished; if greater, so large and disproportionable as not to be endured.