The Notebooks of Leonardo Da Vinci — Volume 2 eBook

This eBook from the Gutenberg Project consists of approximately 486 pages of information about The Notebooks of Leonardo Da Vinci — Volume 2.

The Notebooks of Leonardo Da Vinci — Volume 2 eBook

This eBook from the Gutenberg Project consists of approximately 486 pages of information about The Notebooks of Leonardo Da Vinci — Volume 2.

should have depreciated that solar body, saying that it was of the nature of incandescent stone, and the one who opposed him as to that error was not far wrong.  But I only wish I had words to serve me to blame those who are fain to extol the worship of men more than that of the sun; for in the whole universe there is nowhere to be seen a body of greater magnitude and power than the sun.  Its light gives light to all the celestial bodies which are distributed throughout the universe; and from it descends all vital force, for the heat that is in living beings comes from the soul [vital spark]; and there is no other centre of heat and light in the universe as will be shown in Book 4; and certainly those who have chosen to worship men as gods—­as Jove, Saturn, Mars and the like—­have fallen into the gravest error, seeing that even if a man were as large as our earth, he would look no bigger than a little star which appears but as a speck in the universe; and seeing again that these men are mortal, and putrid and corrupt in their sepulchres.

Marcellus [Footnote 23:  I have no means of identifying Marcello who is named in the margin.  It may be Nonius Marcellus, an obscure Roman Grammarian of uncertain date (between the IInd and Vth centuries A. C.) the author of the treatise De compendiosa doctrina per litteras ad filium in which he treats de rebus omnibus et quibusdam aliis.  This was much read in the middle ages.  The editto princeps is dated 1470 (H.  MULLER-STRUBING).] and many others praise the sun.

881.

Epicurus perhaps saw the shadows cast by columns on the walls in front of them equal in diameter to the columns from which the shadows were cast; and the breadth of the shadows being parallel from beginning to end, he thought he might infer that the sun also was directly opposite to this parallel and that consequently its breadth was not greater than that of the column; not perceiving that the diminution in the shadow was insensibly slight by reason of the remoteness of the sun.  If the sun were smaller than the earth, the stars on a great portion of our hemisphere would have no light, which is evidence against Epicurus who says the sun is only as large as it appears.

[Footnote:  In the original the writing is across the diagram.]

882.

Epicurus says the sun is the size it looks.  Hence as it looks about a foot across we must consider that to be its size; it would follow that when the moon eclipses the sun, the sun ought not to appear the larger, as it does.  Then, the moon being smaller than the sun, the moon must be less than a foot, and consequently when our world eclipses the moon, it must be less than a foot by a finger’s breadth; inasmuch as if the sun is a foot across, and our earth casts a conical shadow on the moon, it is inevitable that the luminous cause of the cone of shadow must be larger than the opaque body which casts the cone of shadow.

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The Notebooks of Leonardo Da Vinci — Volume 2 from Project Gutenberg. Public domain.