Note on light cast through a round aperture
A struck-through two-line query in Leonardo's hand; the rest is another hand
The only transcribed passage is a two-line note in Leonardo's hand, struck through, set in the left margin a little above the middle of folio 103v; the surrounding text on the leaf is in another hand and was left out of the transcription. In it he poses a question about a round aperture ('spiracle') and a long light, asking whether the light's cast ('percussion') will be long, an optics-of-apertures problem. The facing leaf, folio 98r, is nearly blank apart from faint show-through and its folio number.
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Round aperture and the length of the cast light
Leonardo notes to himself: of the round aperture and the long light, will the impact, the patch of light cast, be long? The two lines are struck through and stand in the left margin above the middle of the sheet.