Curved mirrors and throwing-engine mechanisms
A visual-ray diagram of how domed and convex mirrors shrink, enlarge and invert images
The top-left corner carries a faint ray diagram headed 'the nature of mirrors', with the letters a b, e d, c f, h g, m and n p tracing how images behave in curved mirrors. Leonardo explains that a domed mirror shrinks an object, a convex mirror enlarges it, and an object beyond the mirror's centre is thrown back inverted because the images must travel in straight lines. The rest of the sheet is filled with lightly drawn throwing-engine mechanisms, including a screw press and a large circular geared platform. These machines are labelled only as armi da lancio (throwing weapons) and carry no transcribed text.
On this page
Ray diagram of curved mirrors (a b, c d, e f, m, n p)
Setting the line a b before the domed mirror, the image lines converge to its centre and a b shrinks to the size of c d. Before the convex mirror the line h m grows to c f, its images diverging from the centre. An object beyond the centre g, like n p, is carried to the mirror at e f upside down, so that n goes to f and p to e.
Throwing engines drawn on the right
The right and lower parts of the sheet are given over to throwing weapons, sketched faintly in metalpoint. No text accompanies them beyond the heading armi da lancio.
Screw press and circular geared platform
Among the throwing-engine studies are a tall screw-and-frame mechanism resembling a press and a large circular platform carrying radial arms about a central hub. Both are drawn only in faint outline.