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undertook to report further upon it. Some forms of crystal 

 were exhibited, producing novel effects by polarised light. 



Mr. Lynde exhibited a line specimen of copper ore, with 

 jasper, from Cornwall, the colours of which, when illuminated 

 with the Lieberkiihn, were very gorgeous. 



Mr. Latham exhibited the ovary of a flea, and portions 

 of the skin and teeth of the dogfish. 



Mr. Heys exhibited specimens, mounted specially for the 

 Lieberkiihn, of various seeds, hairs, and glands of plants; 

 the tesselated spines on the Symphytum asperrimum, or 

 rough comfrey, and the ruby coloured oil glands of the 

 origamme onites, glowing, like precious stones, with the 

 reflected light from above the object, were very much admired. 

 For certain classes of objects no illumination can compare 

 with that of the Lieberkiihn in the use of the binocuku- 

 microscope, and side lights may be obtained, to some extent 

 all around the object, by manipulation with the mirror. 



