Page:Mathematical collections and translations, in two tomes - Salusbury (1661).djvu/133

 are of two kinds: some have respect to the accidents Terrestrial, without any relation to the Stars, and others are taken from the Phænomena and observations of things Cœlestial. The arguments of Aristotle are for the most part taken from things neer at hand, and he leaveth the others to Astronomers; and therefore it is the best way, if you like of it, to examine these taken from experiments touching the Earth, and then proceed to those of the other kind. And because Ptolomy, Tycho, and the other Astronomers and Philosophers, besides the arguments of Aristotle by them assumed, confirmed, and made good, do produce certain others; we will put them all together, that so we may not answer twice to the same, or the like objections. Therefore Simplicius, choose whether you will recite them your self, or cause me to ease you of this task, for I am ready to serve you.

It is better that you quote them, because, as having taken more pains in the study of them, you can produce them with more readinesse, and in greater number.

All, for the strongest reason, alledge that of grave bodies, which falling downwards from on high, move by a right line, that is perpendicular to the surface of the Earth, an argument which is held undeniably to prove that the Earth is immoveable: for in case it should have the diurnal motion, a Tower, from the top of which a stone is let fall, being carried along by the conversion of the Earth, in the time that the stone spends in falling, would be transported many hundred yards Eastward, and so far distant from the Towers foot would the stone come to ground. The which effect they back with another experiment; to wit, by letting a bullet of lead fall from the round top of a Ship, that lieth at anchor, and observing the mark it makes where it lights, which they find to be neer the * partners of the Mast; but if the same bullet be let fall from the same place when the ship is under sail, it shall light as far from the former place, as the ship hath run in the time of the leads descent; and this for no other reason, than because the natural motion of the ball being at liberty is by a right line towards the centre of the Earth. They fortifie this argument with the experiment of a projection shot on high at a very great distance; as for example, a ball sent out of a Cannon, erected perpendicular to the horizon, the which spendeth so much time in ascending and falling, that in our parallel the Cannon and we both should be carried by the Earth many miles towards the East, so that the ball in its return could never come neer the Peece, but would fall as far West, as the Earth had run East. They againe adde a third, and very evident experiment, scilicet, that shooting a bullet point blank (or as Gunners say, neither above nor under metal) out of a Culverin towards the East, and afterwards another,