Forked shadows from a pyramidal opaque body
A body lit through thick branches casts many shadows; opaque bodies of varied diameter yield forked shade.
The note remarks that a body lit by sunlight passing through the thick branchings of trees casts as many shadows as there are branches between it and the sun. Diagrams treat a luminous body smaller than the opaque one, and a single light set against three opaque bodies of differing diameter, with two propositions and a comment on when a pyramidal opaque body throws a forked (biforcate) shadow. The page continues Notebook C's analysis of how light and shade behave at the boundaries of bodies.
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As many shadows as branches between sun and body
A body illuminated by the sun's rays passing through the thick branchings of plants casts as many shadows as the number of branches interposed between the sun and itself. Each branch acts as a separate occluder of the light.
Luminous body smaller than the opaque body
The upper figure shows a light source smaller than the opaque body it faces, so that the cone of shade widens away from the light. This is the limiting case before the larger opaque bodies of the lower diagram.
When a pyramidal opaque body makes a forked shadow
The shadowy rays born from a pyramidal opaque body strike in a forked figure of varied darkness at its points. When the light is larger than the body's apex but smaller than its base, the impact is a forked shadow of varying darkness; a body partly smaller, partly equal, and partly larger than the light thus divides its shade.