136 THE MINUTE ANATOMISTS 



them ; they loved to work out special mechanisms, the 

 sting of a bee, the barbs of a feather, the claw of a 

 spider, the spore-case of a fern ; in a word, their biology- 

 was unmethodical. The work of Swammerdam, on the 

 other hand, exhibits concentrated effort, while Grew, 

 a man of far inferior power, devoted himself almost 

 entirely to the structure of the higher plants. In the 

 eighteenth century, when the microscope had become an 

 ordinary biological appliance, the best of the naturalists 

 who employed it set narrow limits to their inquiries ; 

 Lyonet, for example, was accustomed to proceed from 

 one definite investigation to another one of the same 

 kind. 



THE DISCOVERY OF THE MICROSCOPE 

 Perhaps the first mention of anything that can be 

 called a magnifying glass is to be found in Seneca, who 

 speaks of a glass ball filled with water, and used to make 

 small letters larger and clearer.^ A passage in Pliny, 

 which has been thought to describe Nero's emerald lens, 

 relates, not to a lens, but to a mirror. Prof Govi, an 

 eminent Italian physicist, who has carefully examined 

 all the accessible evidence,^ finds no mention of crystal 

 lenses earlier than the Opus Majus of Eoger Bacon 

 (1276), where they are described as instruments "useful 

 to old men and to those whose sight is weakened, for 

 by this means they will be able to see the letters 

 sufficiently enlarged, however small they may be." 

 Govi considers Eoger Bacon to be the inventor of 

 convergent lenses, and therefore of the simple micro- 

 ti. Annaei Senecce ad Lucilium Natiiralium QucBstionum Libri, I, vi, 5. 



" The Corn-pound Microscope invented by Galileo {Atti B. Accad. Sci. Fis. 

 Nat. Napoli, Set. II, Vol. II, 1888. Translated in Jour. Roy. Micr. Soc. 

 1889, pp. 574-598). The present account of the discovery of the microscope- 

 is based upon this memoir. 



