ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 553 



MICROSCOPY 

 A. Instruments J Accessories, etc.* 

 (1) Stands. 



Cornell's Micro-telescope. f — To all microscopists the knowledge 

 that their insstrumeiits may be readily converted into telescopes of high 

 power at small cost will be extremely interesting. The principle of this 

 invention is due to A. Cornell, of Tonbridge, Kent, and resides in the 

 combination with an ordinary mounted Microscope of a telescopic ob- 

 jective and a "pin-hole." This combination produces an extremely 

 sharp inverted image in the plane of the Microscope stage, the inversion 

 being corrected by the Microscope element of the combination. 



The attachment for converting a Microscope into the telescope shown 

 at figs. 92 and 'JH, consists of a draw-tube a carrying suitable objective, 



Fig. 92. 



and containing a series of diaphragms for stopping down the Hght. 

 These diaphragms are so proportioned that the amount of light is main- 

 tained through acute angles by concentration ; as, for instance, when 

 using an object-glass of 7-in. focal length. These graduated diaphragms 

 provide for extremely sharp definition. Although the focal angle is 



* This subdivision contains (1) Stands ; (2) Eye-pieces and Objectives ; (3) 

 Illuminating and other Apparatus ; (4) Photomicrography ; (5) Microscopical 

 Optics and Manipulation ; (6) Miscellaneous. 



t Knowledge, xxxv. (1912) p. 345 (2 figs,). 



October 16th, 191:i 2 P 



