' GALILEO'S ' AND CAMPANI'S MICROSCOPES 



127 



after and shown on p. 139. A lens is mounted in a central aperture 

 in a polished concave metal reflector. Descartes apparently devised 

 another and much more pretentious instrument, but it appears im- 

 practicable and could never 

 have existed save as a sugges- 

 tion. But he appears to have 

 IK -en the first to publish figures 

 and descriptions for grinding 

 and polishing lenses. 



In the Museo di Fisica there 



FIG. 92. Galileo's microscopes. 

 ? Campani or later. 



FIG. 93. Campani's microscope (1660)? 



are two small microscopes which 

 it is affirmed have been handed 



down from generation 



to gene- 



ration since the dissolution of 

 the Accademia del Cimento in 

 1667, with the tradition of 

 having been constructed 

 (Galileo. They are shown 



by 



111 



fig 



92, but from the superiority of construction of these instru- 

 ments it is very improbable that they belong to the days of Galileo, 

 who died in 1642 ; and there is a specially interesting compound 



