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undertook to report further upon it. Some forms of crystal 
were exhibited, producing novel eftects by polarised light. 
Mr. Lynde exhibited a fine 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, wdth 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 binocular 
microscope, and side lights may be obtained, to some extent 
all around the object, by manipulation with the mirror. 
