JOURNAL 



OF THE 



ROYAL MICROSCOPICAL SOCIETY. 



AUGUST, 1915. 



TRANSACTIONS OF THE SOCIETY. 



VI. — The Dawn of Microscopical Discovery. 

 By Charles Singer. 



{Read January 20, 1915). 

 Figs. 33 to 48. 



The history of microscopical discovery may be conveniently 

 divided into three main epochs : — 



1. The Pioneer period, extending to about 1660. 



2. The Classical period, covering halt* a century or more from 

 about 1660, and including the work of the great microscopists, 

 Hooke, Grew, Malpighi, Leeuwenhceck and Swammerdam. 



3. The Modern period, dating from the optical discoveries of 

 Newton. 



It is with the first of these periods that we shall mainly deal 

 in the following pages. 



The earliest microscopical observation known is that of Seneca 

 (circa a.d. 63), who in his " Quoestiones Naturales " assures us 

 that "Letters, however small and dim, are comparatively large 

 and distinct when seen through a glass globe filled with water." * 

 This is, however, an isolated observation. 



The properties of curved reflecting surfaces, and even to 

 some extent of lenses, were known to the ancients, and to 

 some mediaeval writers, such as Roger Bacon. t The invention 



* Lucius Annaeus Seneca, " Qurestiones naturales," Lib. i., ch. 6. 



t For Roger Bacon's knowledge of optics see " The ' Opus Majus ' of Roger 

 Bacon, with Introduction," by J. H. Bridges, Oxf., 1897, p. lxix. ft, and parts iv. 

 and v. of the " Opus Majus " itself. Also E. Wiedemann and S. Vogl in " Roger 

 Bacon, Essays . . . collected and edited by A. O. Little," Oxf., l'J14. 



Aug. 18th, 1916 z 



