The 



Romance of the Microscope 



CHAPTER I 



THE EARLY DAYS OF THE MICROSCOPE 



IT is certain that lenses were used as early as the 

 thirteenth century, and it is probable that they 

 date back to far earlier times. The ancient gem 

 cutters probably used spheres of glass filled with water 

 as magnifiers, their work could hardly have been ac- 

 complished without some artificial aid. We know, 

 from early writings, that burning glasses were used 

 by physicians in their work, and Seneca, the author, 

 who wrote in a.d. 63, says : " Letters, however small 

 and dim, are comparatively large and distinct when 

 ^?:en through a glass globe filled with water." 



Euclid, whose name at least is familiar to every- 

 one, was, as shown by his writings, perfectly well 

 acquainted with the fact that curved mirrors may 

 be used to magnify objects, and that was so long ago 

 as the third century B.C. Convex glasses, used as 

 spectacles, were first mentioned by Bernard de 

 Gordon, abaut 1307, but, as far as we know, they 



17 B 



