Ch. XII] HISTORY OF LENSES AND MICROSCOPES 



443 



tion of eye-glasses (oculars) for such telescopes as may be applied to mathe- 

 matical instruments. (Pp. 94-98, 1 plate. In Vol. LXXIII, 1783.) 



Risner, J. — See Alhazen. 



Scheiner, C. — Rosa Ursinae, 1826-1830. Action of the eye, p. 108; The tele- 

 scope and microscope and projection therewith, p. 130. 



Spencer & Tolles. — See Krauss, Trans. Amer. Micr. Soc, 1901, pp. 19-29. 

 History of their contributions to microscopy. 



Tolles-Spencer. — See Cox, Trans. Amer. Micr. Soc. 1884, pp. 5-39; Krauss, 

 Trans. Amer. Micr. Soc. 1901, pp. 19-29; Mayall, Hist. Micr. pp. 95-96. 



Walgensten's magic lantern. Milliet de Chales, q.v. 



Young, Thomas. — On the mechanism of the eye, 1800, in Philos. Trans. Roy. 

 Soc. London, 1801, pp. 23-88. On pp. 39-40 he describes astigmatism, and 

 shows that it can be corrected by tilting the spectacles. See Airy. 



Zahn, J. — Oculus artificialis teledioptricus, etc., 1702. Many figures of optic 

 apparatus at that time. 



REDUCING GLASS 

 Convex / \ Convex 



Microscope 



Microscope 



