“...let LN represent a glass biconvex lens, with centres of curvature at C and C’, and AB, the incident ray.” -Avery 1895
Elroy M. Avery School Physics (New York: Sheldon and Company, 1895) 358
2400×896, 125.6 KiB
1024×382, 23.5 KiB
640×238, 13.0 KiB
320×119, 5.5 KiB