Archimedes Texts

SALV. The doubt is ingenious and worthy of consideration;
and as it but just now came into your mind unawares, so I will
like wise answer with what first comes into my thoughts, and it may
happily fall out, that by thinking more upon it, I may stumble
upon a better reply. But before, that I labyrinth my self any far
ther, it would be necessary, that we assure our selves by some ex
periment, whether your objection prove in effect, what it seemeth
to conclude in appearance; and therefore taking once more the
same paper, and making it to incline, by bending a little part
thereof upon the remainder, let us try whether exposing it to the
Sun, so that the rayes of light fall upon the lesser part directly,
and upon the other obliquely; this which receiveth the rayes direct
ly appeareth more lucid; and see here by manifest experience,
that it is notably more clear. Now if your objection be conclusive,
it will follow, that stooping with our eye so, that in beholding
the other greater part, less illuminated, in compression or fore
shortning, it appear unto us no bigger than the other, more shining;
and that consequently, it be not beheld at a greater angle than
that; it will necessarily ensue, I say, that its light be encreased, so
that it do seem to us as bright as the other. See how I behold, and
look upon it so obliquely, that it appeareth to me narrower than
the other; but yet, notwithstanding its obscurity, doth not to
my perceiving, at all grow clearer. Try now if the same succeed
to you.

SAGR. I have look't upon it, and though I have stooped with
my eye, yet cannot I see the said superficies encrease in light or
clarity; nay me thinks it rather grows more dusky.

SALV. We are hitherto confident of the invalidity of the ob
jection; In the next place, as to the solution, I believe, that, by
reason the Superficies of this paper is little lesse than smooth, the
rayes are very few, which be reflected towards the point of inci
dence, in comparison of the multitude, which are reflected to
wards the opposite parts; and that of those few more and more
are lost, the nearer the visive rayes approach to those lucid rayes
of incidence; and because it is not the incident rayes, but those
which are reflected to the eye, that make the object appear lu
minous; therefore, in stooping the eye, there is more lost than got,
as you your self confesse to have seen in looking upon the obscu
rer part of the paper.

SAGR. I rest satisfied with this experiment and reason: It re
mains now, that Simplicius answer to my other question, and tell
me what moves the Peripateticks to require this so exact rotundity
in the Cœlestial bodies.