"...let LN represent a glass biconvex lens, with centres of curvature at C and C', and AB, the incident ray." -Avery 1895

Refraction of Light through Bi Convex Lens

"...let LN represent a glass biconvex lens, with centres of curvature at C and C', and AB, the incident…

"Showing how an object is refracted through a biconvex lens." -Avery 1895

Object Refracted through Biconvex Lens

"Showing how an object is refracted through a biconvex lens." -Avery 1895