Reflection at the surface of water and concave mirrors
Incident rays, mutual mirroring of air and water, with personal reminders
This sparse sheet gathers optical notes: incident rays are said to pass first through the center of concave mirrors before reaching their surfaces, and the polished surfaces of transparent bodies mirror whatever faces them, so that what lies under water is reflected in the bordering surface of the air and what is in the air is reflected in the surface of the water (texts 1, 3). A marginal note observes that the farther a larger body recedes from a smaller one, the less of it is seen (text 2). Among these statements Leonardo interleaves personal reminders, including making a stick that breaks (appears broken) in the water of a trough on Sunday morning and a reflection on how he has spent his time (text 1). Faint ray diagrams appear on the left folio, and the right folio carries further untranscribed writing beside its figures (text 4).
On this page
Incident rays and the center of concave mirrors
All incident rays pass first through the center of concave mirrors before they reach their surfaces. The note accompanies faint diagrams of converging rays.
Mutual mirroring at the boundary of air and water
The smooth surfaces of transparent, polished bodies always mirror the objects that face them. Thus whatever is beneath the water is reflected in the surface of the air that borders that water, and whatever is in the air is reflected in the surface of the water that borders that air.
A larger body seen less as it recedes
The more a larger body draws away from a smaller one, the less of it the smaller sees. The remark stands as a brief rule of vision in the upper right margin.
Reminders and an autobiographical jotting
Between the optical statements Leonardo sets down memoranda to himself: to make the stick that breaks in the water of the trough on Sunday morning, and the unfinished reflection 'Having spent my time in things which...' followed by 'If you will be under the water...'.