MR. W. H. HEYS ON THE KALOSCOPE. 235 



their being moved about without disturbing the position of 

 any of the glasses belonging to the lower set which may 

 happen to be in use at the same time. 



The kaloseope can be used for a very considerable 

 variety of objects; and a great number^ which do not 

 polarize, are made to disclose all the beauties of polarized 

 objects. For instance, suppose the anthers of the mallow, 

 with their pollen, to be the object under view; we place 

 the slide upon the stage, arrange it as a transparent object, 

 and also throw condensed light upon the upper surface; 

 then placing the kaloseope in position, or so as to allow of 

 a red glass belonging to the lower set being interposed 

 between the lamp and the mirror, the ground upon which 

 the object is seen is coloured crimson. By next adjusting 

 a green disc belonging to the upper set (green being the 

 complementary colour of red) so that its tint shall be 

 thrown through the bulFs eye, a beautiful green hue is 

 cast upon the object, illuminating it in a perfectly novel 

 and most valuable manner, the anthers and pollen appear- 

 ing intensely green, while the ground beneath them is 

 crimson. These colours may be changed for others at the 

 pleasure of the observer. 



It will soon be discovered by any one using the kalo- 

 seope that nearly all objects viewed by it appear so much 

 in relief that we might suppose them to be viewed through 

 a stereoscope. For observing anthers, jointed hairs, oil 

 glands and vegetable sections in general, but especially 

 sections of wood, this instrument will be found, accordingly, 

 of singular use. Some objects, moreover, which before 

 were attractive only to the scientific botanist, are trans- 

 formed into pictures of such beauty that they cannot fail 

 to rank in future with the most popular and esteemed 

 microscopic preparations. The calyx of the moss-rose is a 

 good example of both these results. Under the ordinary 

 modes of illumination it is a mere entanglement of coarse 



