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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 he had 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 work on the 

 Microscope (London, 1785), with many engravings of 

 vegetable forms in crystals of manna, salts of antimony, 

 copper, &c. 



Mr. Brotheks exhibited a drawing of a small animal he 

 found leaping on the surface of the water in his aquarium, 

 supposed to be identical with the species of Podura found 

 last year by Mr. Lynde. 



