The Species of Objects Fill All the Air
Diagrams of luminous rays, triangles of illumination, and a column of calculations
This densely written sheet argues Leonardo's theory that the 'species' (images) of every visible object are diffused whole throughout all the air and present in each of its parts. Several ray diagrams, lettered from a to L, accompany the claims, including a triangle whose luminous base a b lights the opposite angle to the highest degree. A polemical note denies that any spiritual or transparent thing could see, since sight requires a dense, opaque instrument and an aperture. A column of numbers and arithmetic operations occupies the lower right.
On this page
Images of every object are diffused through all the air
The species of any visible object are all infused throughout the whole of the opposed air and are all separated in every part of that same air. This is the governing principle of the sheet, restated in several forms.
Every object is seen from every point of the air
Beside a ray diagram lettered f d a b g e c, Leonardo states that all objects seen from a single point are seen again from that same point, and that objects infuse their species into all the air that sees them. All the air that is seen by an object also sees it.
Triangle of illumination a c b
The triangle a c b, by means of its luminous base a b, lights the angle c to the highest degree of illumination. A second triangle d f e receives as much less light at f as its base d e is smaller than the base a b of the first, tying brightness to the size of the luminous base.
Nothing can see without a dense, opaque organ
Nothing is seen that does not send its species through the air, because that is what makes it visible. No spiritual or transparent thing can see anything set before it, for sight requires a dense and opaque instrument; and if a thing has such an instrument it is not a spirit.
Vision requires an aperture
A proof that nothing can be seen except through an aperture, through which passes the air laden with the species of objects; these intersect at the dense, opaque edges of the aperture. A bodiless thing can perceive neither figure nor colour, lacking the dense instrument whose aperture lets the species imprint their colours and shapes.
Column of numbers and arithmetic operations
The lower right of the sheet carries a column of figures and additions unrelated to the optical text. Only the numerals themselves are recorded.