The Manuscripts of Leonardo da Vinci, Vol. 4

[WATER (9TH BOOK) — THE SUN AND THE AUTHORS].

5. — Book Nine
Of the water that passes through a reservoir reservoir; original: "bottino" — a cistern or water conduit of which the walls are full of vents vents; original: "spiracu li" — small openings or apertures of various sizes, shapes, and positions at different heights, varying from the entrance to the exit and vice versa; and also of the reservoir of various shapes, depths, lengths, and widths; and of waters more or less powerful, fast, thick, or thin.

If you look at the stars without their rays By "rays," Leonardo refers to the visual "twinkling" or diffraction patterns seen by the naked eye. (as is done by viewing them through a small hole made with the fine tip of a slender needle, placed so it almost touches the eye), you will see those stars to be so tiny that nothing seems smaller. Truly, the great distance causes a reasonable reduction in their size, even though many of them are many times larger than the "star" that is the earth with its water. Now, think what our own star meaning Earth would look like at such a distance, and then consider how many stars could be placed, in both length and width, between those stars which are scattered throughout that dark space. I cannot help but blame many of the ancients who said that the sun had no other size than what it appears to be; among these was Epicurus. I believe he derived such a reason from a light placed in our atmosphere equidistant to the center of the person seeing it; whoever sees it never sees it diminished in size at any distance, and the [ The continuation is on Folio 4 verso ] original: "le ragi [ La suite au folio 4 verso ]"

5. — Book Nine [ 9th ]:
Of the water that passes through a reservoir whose walls are full of various vents in size; shapes and places, with various heights, varying from the entrance to the exit, and reciprocally, and also: Of the reservoir of various shapes, depths, lengths and widths, and: Of waters more or less powerful, fast, large and small Referencing J.-P. Richter, Vol. II, p. 491, "Bibliography". Below the first paragraph is a draft in red chalk..

PRAISE OF THE SUN.

If you look at the stars without rays (as one does by seeing them through a small hole made with the extreme tip of a fine needle, and placed almost touching the eye), you will see these stars being so tiny that nothing can appear smaller, and truly the long distance gives them a reasonable diminution, although there are many which are a very great number of times larger than the star which is the earth with the water. Think now what our star would appear at such a great distance, and then consider how many stars one would put, both in length and width, between those stars which are sown in the shadowy space. I can never help but blame many of those ancients who said that the sun has no other greatness than that which it shows; among them was Epicurus. And I believe that such a reason [idea] is drawn from a light placed in our air equidistant to the center [of the earth]; whoever sees it never sees it diminished in size at any distance and the [continued on folio 4 verso] Referencing Libri, Vol. III, Note XIV. — J.-P. Richter, Vol. II, no. 879. Dr. M. Jordan, p. 76..

[CENTERS OF GRAVITY. — HOW THE STARS ARE SEEN. — CHARLATANS].

[ Figure: ] c a b d e f f
Although b is the center of accidental gravity accidental gravity; original: "grauita accidentale" — the weight of an object relative to its position on a balance of the pyramid e, and the tip counterbalances the base just as much, the true center of natural gravity, which is at a, cannot, I believe, be as close to the central line as the center of the cube is. Because it is further from the balance point of the pyramid c e, it would happen that when you balanced the pyramid at that center of natural gravity, the part toward the tip would be heavier than the part toward the base; and the excess that the weight of the tip had over the weight of the base would be discharged onto the cube.

The stars are seen by night and not by day because we are beneath the thickness of the air, which is full of infinite particles of moisture. Each of these, when struck by the rays of the sun, yields its own brightness, and so these innumerable splendors original: "invmerabilis plendori" occupy [the view of] those stars; if such air were not there, the sky would always show us the stars within its darkness.

[ In the margin: ] And many make a shop of deceits and feigned miracles, deceiving the foolish multitude; and if no one discovered themselves as a knower of their deceits, they would impose them [upon everyone] Leonardo is critiquing "charlatans" or street magicians/merchants who use tricks to exploit the public..

[ Figure: ] c a b d e f f
Although b is the center of the accidental gravity of the pyramid e, and the point counterbalances the base as much as, the true center of natural gravity, which is in a, cannot, I believe, be so close to the central line as is the center of the cube. Because it is further from the equilibrium of the pyramid c e, it would happen that when you balanced the pyramid in this center of natural gravity, the part on the side of the point would be heavier than the part on the side of the base, and the excess that the weight of the point would have over the weight of the base would be discharged onto the cube The preceding text and the figure are in red chalk..

The stars are seen by night and not by day, because we are under the thickness of the air, which is full of infinite [an infinite number of] particles of moisture. Each of them, when it is struck by the rays of the sun, resplends [is lit up], and thus innumerable splendors occupy [lit particles hide] these stars; and if there were not this air, the sky would always show us the stars in its darkness The writings of L. de V., by Ch. Rav.-Moll., p. 61; J.-P. Richter, Vol. II, no. 911..

[ In the margin: ] And many make a shop of deceits and feigned miracles, deceiving the foolish multitude, and if no one discovered themselves as a knower of their deceits, they would place them [? make people believe them forever] The writings of L. de V., by Ch. Rav.-Moll., p. 61; J.-P. Richter, Vol. II, no. 1208. Dr. M. Jordan, p. 76..