68 Intelligence and Miscellaneous Articles. 



crystallized once or twice from aether slightly alcoholized, this acid 

 melts at 140° Fahr., and becomes a radiated mass on cooling ; this 

 acid, after being fused, yielded by analysis, — 



Carbon 751 



Hydrogen 12'8 



Oxygen 12*1 



100- 



which gives as the formula C 17 H 17 O 2 , and the substance produced 

 was therefore margaric acid. The solid carburetted hydrogen which 

 accompanies the above substance is paraffin, as shown by the expe- 

 riments of M. Ettling. — Ann. de Ch. et de Phys., Nov. 1845. 



ANALYSIS OF PHOSPHATE OF ALUMINA. BY M. A. DELESSE. 



M. Danhauser discovered at Bernay, near Epernay, a white sub- 

 stance, considerably resembling alumina dried on a filter ; it invested 

 a gangue coloured by the oxides of iron and manganese, and ap- 

 peared to belong to the plastic clay formation. Several collections 

 in Paris contain specimens of it, but that examined by M. Delesse 

 contained phosphoric acid. 



In the closed tube this substance blackens and yields much water, 

 containing bituminous matter ; it is acid, reddens litmus paper, and 

 appears also to corrode glass slightly, which may indicate the pre- 

 sence of a little hydrofluoric acid. In the outer flame of the blow- 

 pipe, the black colour produced by the carbon of the organic matter 

 disappears and the substance becomes white ; it is infusible. With 

 the salt of phosphorus it readily dissolves, and a very transparent 

 bead is formed ; with carbonate of soda this substance swells, but 

 does not dissolve ; with nitrate of cobalt it yields a fine blue colour. 



When not calcined this substance dissolves entirely and with the 

 greatest facility in acids ; it also dissolves, but with difficulty, in pot- 

 ash. .After calcination, it is scarcely and with difficulty acted upon 

 by acids. 



It will be observed that the substance possesses all the properties 

 of pure alumina, and, as already observed, it has the appearance of 

 it ; the presence of phosphoric acid was, however, ascertained by the 

 process of Vauquelin and Thenard ; it also contains a little lime, 

 which is undoubtedly in the state of carbonate, for when acted upon 

 by acids there is a disengagement of gas. 



After several hours' drying, so as to expel the hygrometric moist- 

 ure, the loss amounted to about 10 per cent; and by analysis the 

 substance yielded, — 



Phosphate of alumina 46 



Water and organic matter 49 



Carbonate of lime and loss .... 5 



100 



M. Delesse states that he did not possess a sufficient quantity of 

 the mineral to determine the quantity of phosphoric acid ; but it is 



