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Mr. Heys, of Hazel Grove, read a Paper " On the Kalo- 

 scope," his newly invented instrument for the use of coloured 

 light in the examination of objects under the microscope. 

 This the Author eifects by two sets of four discs each of 

 differently coloured glass, 21 inches in diameter, mounted on 

 a stand 12 inches high, one set of which is placed between 

 the light and the bull's eye condenser, and the other between 

 the light and the mirror, underneath the stage, each disc 

 having an independent motion, so that the light can be 

 transmitted through one or more of both sets at the same 

 time; when the object appears of the colours refracted and 

 reflected through the discs. 



One of the important uses of the instrument is the protec- 

 tion of the eye from injury occasioned by the use of common 

 artificial light. 



Many objects which do not polarise, by the kaloscope are 

 made to disclose the beauties of polarised light ; for instance, 

 the anthers of the mallow, with their pollen, when viewed by 

 means of red light below the stage, and at the same time 

 green light (the complementary colour) through the con- 

 denser, appear of a beautiful green colour on a red or crimson 

 ground. 



The Author observes that some objects, viewed by 

 means of the kaloscope, appear in such relief that they might 

 be supposed to be seen through a stereoscope ; these are 

 anthers, jointed hairs, oil-glands, and vegetable sections in 

 general. The calyx of the moss-rose is alluded to, under 

 ordinary illumination, as a mere entanglement of fibres with 

 dark beads.; but by this method it is transformed into a 

 stereoscopic branch, with glittering glands at its extremities. 



Sections of wood, spines of echini, &c., will be found as 

 beautiful as with the polariscope ; but, by another arrange- 

 ment, details are brought out not observable with the latter 

 instrument. A black surface being placed below the stage, 

 coloured light is thrown very obliquely from the mirror, and 



