I ;o THE HISTOKV AND DEVELOPMENT OF THE 3IICKOSCOPE 



magnification from 41 to 143 diameters. Instead of the usual bi- 

 convex eye-lens, t\\o plano-convex lenses were applied with their 

 convex surfaces in contact, by which he claimed to obtain a much 

 Hatter field. .Mr. M avail found in the Museo Copernicano at Rome 

 a micro.-cope answering so closely to this description that he does 

 not hesitate to refer its origin to Divini. He made the sketch of 



it given in fig. 95. 

 But the optical con- 

 struction had been 

 tampered with and 

 could not be esti- 

 mated. 



Cherubin d'Orleans 

 published, in 1671, a 

 treatise containing a 

 design for a micro- 

 scope, of which fig. 

 96 is an illustration. 

 The scrolls were of 

 ebony, firmly at- 

 tached to the base 

 and to the collar 

 encircling the fixed 

 central portion of the 

 body-tube. An ex- 

 terior sliding tube 

 carried the eye-piece 

 above on the fixed 

 tube, and a similar 

 sliding tube carried 

 the object-lens below, 

 these sliding tubes 

 serving to focus the 

 image and regulate 

 (within certainlimits) 

 the magnification. 

 He also suggested a 

 screw arrangement 

 to lie applied beneath 

 the stage for focus- 

 sing. He devised, or 

 recommended, seve- 

 ral combinations of 



'roans' compound microscope lenses for the optical 



part of the micro- 



to combinations of three or four separate lenses 

 ibjects could be seen erect, which he considered -much to 

 be preferred. 



ented " binocular form of microscope and published 



La Vision Parfaite,' in 1677. It consisted of two 



joined together in one setting, so as to be 



