Crossing Light Rays and Paired Shadow Triangles
Rays from a fan-shaped source cross at a point, casting two hatched shadow regions
A wide fan or arc of rays occupies the upper half of the sheet and narrows to a single crossing point at the centre, from which the rays open out again into a mirrored lower half. Two hatched triangular zones of shade form an hourglass about the crossing, bounded by ruled panels at the sides, and two small circles hang below like paired sources or apertures. The figure studies how rays intersecting at a point invert to produce matched regions of light and shade. The framing mirror-written Italian is not transcribed in this bundle, and further untranscribed text is present.
On this page
Rays crossing at a point and their inverted shadows
Straight rays fan down from an arc at the top, converge on a single central point, and spread again below, so that the figure reads as two triangles meeting tip to tip. Diagonal hatching fills the paired shadow regions to either side of the crossing, with small circular marks set below. The construction shows how light passing through a point reverses to cast symmetrical shade.
Explanatory text (untranscribed)
Lines of mirror-written Italian head the page and continue in a block beneath the figure, keyed to the lettered points of the construction. This text is not supplied in the bundle and is not transcribed here.