Page:Mathematical collections and translations, in two tomes - Salusbury (1661).djvu/158

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Dialogue. II.
133

Simpl.Because that the air it self is not moved

Salv.It is requisite then, that the projicient do confer motion on the Air, with which it afterward moveth the project. But if such a motion cannot be impressed [i. e. imparted] it being impossible to make an accident passe out of one subject into another, how can it passe from the arm into the Air? Will you say that the Air is not a subject different from the arm?

Simpl.To this it is answered that the Air, in regard it is neither heavy nor light in its own Region, is disposed with facility to receive every impulse, and also to retain the same.

Salv.But if those penduli even now named, did prove unto us, that the moveable, the lesse it had of gravity, the lesse apt it was to conserve its motion, how can it be that the Air which in the Air hath no gravity at all, doth of it self alone retain the motion acquired? I believe, and know that you by this time are of the same opinion, that the arm doth not sooner return to rest, than doth the circumambient Air. Let's go into the Chamber, and with a towel let us agitate the Air as much as we can, and then holding the cloth still, let a little candle be brought, that was lighted in the next room, or in the same place let a leaf of beaten Gold be left at liberty to flie any way, and you shall by the calm vagation of them be assured that the Air is immediately reduced to tranquilty. I could alledg many other experiments to the same purpose, but if one of these should not suffice, I should think your folly altogether incurable.

Sagr.When an arrow is shot against the Wind, how incredible a thing is it, that that same small filament of air, impelled by the bow-string, should in despite of fate go along with the arrow? But I would willingly know another particular of Aristotle, to which I intreat Simplicius would vouchsafe me an answer. Supposing that with the same Bow there were shot two arrows, one just after the usual manner, and the other side-wayes, placing it long-wayes upon the Bow-string, and then letting it flie, I would know which of them would go farthest. Favour me, I pray you with an answer, though the question may seem to you rather ridiculous than otherwise; and excuse me, for that I, who am, as you see, rather blockish, than not, can reach no higher with my speculative faculty.

Simpl.I have never seen an arrow shot in that manner, yet neverthelesse I believe, that it would not flie side-long, the twentieth part of the space that it goeth end-wayes.

Sagr.And for that I am of the same opinion, hence it is, that I have a doubt risen in me, whether Aristotle doth not contradict experience. For as to experience, if I lay two arrows upon this Table, in a time when a strong Wind bloweth, one towardsthe