Cast Shadow of Spheres and Rays in a Light Chamber
Tangent cones of shadow between light and body, and rays forming a shaded region inside an enclosure
An upper figure joins two plain circles and one shaded sphere with straight tangent lines that fan into a cone, a construction for the shadow an illuminated round body casts. A lower boxed diagram shows a spray of rays running from a cluster of lettered points across an enclosure to a hatched triangular shadow marked near points a, b and c. The sheet is filled top and bottom with Leonardo's mirror-script prose, which the bundle does not transcribe, so further untranscribed text is present. The studies belong to his geometry of light and cast shadow.
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Tangent cone between a light source and a shaded sphere
Two outlined circles and a shaded sphere are linked by straight tangent lines that converge into a cone, with a fainter ghost circle behind. The construction sets out how the boundary rays grazing an illuminated round body define the edges of the shadow it throws.
Rays crossing to a hatched shadow inside a chamber
Inside a rectangular enclosure a fan of straight rays runs from a cluster of lettered points on one side to a hatched triangular shadow against the opposite wall, near points labelled a, b and c. It studies how a beam entering an enclosed space casts a defined shaded patch.