ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 847 



Electro-megaloscope.* — M. E. Dieudonne describes and figures 

 Dr. Boisseau du Bocher's Megaloscope for examining the stomach, 

 bladder, and other internal cavities. A full translation of the original 

 article having been already givcn,"j" we need only add the description 

 of fig. 169, which shows the apparatus for examining the bladder. 



Fig. 169. 



At the lower end of the tube is a lateral aperture closed by a right- 

 angled prism A. Above the prism are two hemispherical lenses B B' 

 with the convex surfaces turned to each other. A diminished image 

 of an object F Fj is formed at //, which serving as an object to the 

 lens C in the upper part of the tube, a second, still diminished, imago 

 is formed at F F 2 . This gives with the Bamsden eye-piece DD' an 

 image F F 3 , a little larger than the original object. 



* La Lumiere Electrique, xix. (1S86) pp. 64-7 (3 figs.). 

 + See this Journal, v. (1S85) p. 1061. 



