Figures & data
Figure 1. Visualization of sine and chord.
Figure 2. Title page of Tyrtov's book.
Figure 3. An explanation of the sine can be found in Tyrtov's treatment of the intensity of light striking a slanted surface.
Figure 4. Refraction in a translucent medium bounded by a plane surface.
Figure 5. Chords of incident and refracted rays of light.
Figure 6. Refraction in a biconvex spherical lens
