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usual rhombic form, and possibly to the subtle electrical or 
galvanic action supposed to be excited during crystallisation. 
Some years ago be bad obtained from solution of bichromate 
of potash, tree-like forms with spreading branches and pendent 
rhomboids, which under the polariscope appeared like a tree 
with gems of rich colours for fruit. 
Mr. Mosley exhibited an edition of Baker’s Avork on the 
Microscope (London, 1785), with many engravings of 
vegetable forms in crystals of manna, salts of antimony, 
copper, &c. 
Mr. Brothers exhibited a draAving of a small animal be 
found leaping on the surface of the Avater in bis aquarium, 
supposed to be identical with the species of Podura found 
last year by Mr. Lynde. 
