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Rh and conequently ome Years mut be ubtracted from their Computation. Obervations eem to have lent a till greater Aitance to our Philoopher. He appears to us tronger when he fights upon his own Ground. know that the Earth, beides its annual Motion which carries it round the Sun from Wet to Eat in the Space of a Year, has alo a ingular Revolution which was quite unknown till within thee late Years. Its Poles have a very low retrograde Motion from Eat to Wet, whence it happens that their Poition every Day does not correpond exactly with the ame Point of the Heavens. This Difference which is o inenible in a Year, becomes pretty coniderable in Time; and in threecore and twelve Years the Difference is found to be of one Degree, that is to ay, the three hundred and ixtieth Part of the Circumference of the whole Heaven. Thus after eventy two Years the Colure of the vernal Equinox which pas'd thro' a fix'd Star, correponds with another fix'd Star. Hence it is, that the Sun, intead

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