Page:Mathematical collections and translations, in two tomes - Salusbury (1661).djvu/330

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Dialogue. III.
303

to confide so much in that which reason dictated to them, as that they have confidently affirmed that the structure of the Universe could have no other figure than that which they designed to themselves. There are also several other very serious and curious doubts, not so easie to be resolved by the middle sort of wits, but yet penetrated and declared by Coperninus, which we shall defer till by and by, after we have answered to other objections that seem to make against this opinion. Now coming to the declarations and answers to those three before named grand Objections, I say, that the two first not onely contradict not the Copernican Systeme,Answers to the three first objections against the Copernican Systeme. but greatly and absolutely favour it; For both Mars and Venus seems unequal to themselves, according to the proportions assigned; and Venus under the Sun seemeth horned, and goeth changing figures in it self exactly like the Moon.

Sagr.But how came this to be concealed from Copernicus, and revealed to you?

Salv.These things cannot be comprehended, save onely by the sense of seeing, the which by nature was not granted to man so perfect, as that it was able to attain to the discovery of such differences; nay even the very instrument of sight is an impediment to it self: But since that it hath pleased God in our age to vouchsafe to humane ingenuity, so admirable an invention of perfecting our sight, by multiplying it four, six, ten, twenty, thirty, and fourty times, infinite objects, that either by reason of their distance, or for their extream smallnesse were invisible unto us, have by help of the Telescope been rendered visible.

Sagr.But Venus and Mars are none of the objects invisible for their distance or smallnesse, yea, we do discern them with our bare natural sight; why then do we not distinguish the differences of their magnitudes and figures?

Salv.In this,The reason whence it happens that Venus and Mars do not appear to vary magnitude so much as is requisite. the impediment of our very eye it self hath a great share, as but even now I hinted, by which the resplendent and remote objects are not represented to us simple and pure; but gives them us fringed with strange and adventitious rayes, so long and dense, that their naked body sheweth to us agrandized, ten twenty, an hundred, yea a thousand times more than it would appear, if the capillitious rayes were taken away.

Sagr.Now I remember that I have read something on this subject, I know not whether in the Solar Letters, or in the Saggiatore of our common Friend, but it would be very good, aswell for recalling it into my memory, as for the information of Simplicius, who it may be never saw those writings, that you would declare unto us more distinctly how this businesse stands, the knowledge whereof I think to be very necessary for the assisting of us to understand that of which we now speak.

Simp.