Page:Mathematical collections and translations, in two tomes - Salusbury (1661).djvu/184

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Dialogue. II.
159

following the birds flight with the piece, is his somewhat anticipating it, taking his aim before it; as also his shooting (as I believe) not with one bullet, but with many small balls (called shot) the which scattering in the air possess a great space; and also the extreme velocity wherewith these shot, being discharged from the Gun, go towards the bird.

Salv.See how far the winged wit of Sagredus anticipateth, and out-goeth the dulness of mine; which perhaps would have light upon these disparities,The answer to the Argument taken from the shots at point blanck towards the East & West. but not without long studie. Now turning to the matter in hand, there do remain to be considered by us the shots at point blank, towards the East and towards the West; the first of which, if the Earth did move, would always happen to be too high above the mark, and the second too low; forasmuch as the parts of the Earth Eastward, by reason of the diurnal motion, do continually descend beneath the tangent paralel to the Horizon, whereupon the Eastern stars to us appear to ascend; and on the contrary, the parts Westward do more and more ascend, whereupon the Western stars do in our seeming descend: and therefore the ranges which are leveled according to the said tangent at the Oriental mark, (which whilst the ball passeth along by the tangent descendeth) should prove too high, and the Occidental too low by means of the elevation of the mark, whilst the ball passeth along the tangent. The answer is like to the rest: for as the Eastern mark goeth continually descending, by reason of the Earths motion, under a tangent that continueth immoveable; so likewise the piece for the same reason goeth continually inclining, and with its mounture pursuing the said mark: by which means the shot proveth true.

But here I think it a convenient opportunity to give notice of certain concessions,The followers of Copernicus too freely admit certain propositions for true, which are very doubtfull. which are granted perhaps over liberally by the followers of Copernicus unto their Adversaries: I mean of yielding to them certain experiments for sure and certain, which yet the Adversaries themselves had never made tryal of: as for example, that of things falling from the round-top of a ship whilst it is in motion, and many others; amongst which I verily believe, that this of experimenting whether the shot made by a Canon towards the East proveth too high, and the Western shot too low, is one: and because I believe that they have never made tryal thereof, I desire that they would tell me what difference they think ought to happen between the said shots, supposing the Earth moveable, or supposing it moveable; and let Simplicius for this time answer for them.

Simpl.I will not undertake to answer so confidently as another more intelligent perhaps might do; but shall speak what thus upon the sudden I think they would reply; which is in effect the same

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