Note 38 — Chapter II · GLENLAIR—CHILDHOOD—1831 TO 1841.
Reading edition
This was afterwards developed into the “zoëtrope” or “wheel of life,”—how far through suggestions of Clerk Maxwell’s, or otherwise, I am unable to say. The lenses which perfect the illusion were certainly added by Maxwell himself. See Problem XX. of Cambridge Tripos Examination, 1869, Thursday, January 7.