ACIPENSER HUSO. 



it is in extensive use for fining by brewers, who prefer it to 

 either of the other sorts, and are the principal consumers of 

 isinglass. 



CHEMICAL AND MEDICAL PROPERTIES AND USES. 



ISINGLASS. Ichthyocolla is not officinal, but it is still much 

 used. The sounds of the perch, some species of the cod, and 

 some other fishes, afford isinglass. The sturgeons, Acipenser 

 sturio, A. ruthenus, A. Guldenstadtii, A. stellatus, and A. huso, 

 from which the best is prepared, are caught in the rivers of 

 Russia, in the Nile, and in the Caspian Sea, and occasionally 

 elsewhere. 



The isinglass is the prepared sound or swimming-bladder. 

 It is taken from the fish, slit open, well washed, and freed from 

 the thin membrane which covers it, then beaten, exposed to 

 stiffen a little in the air, rolled and fixed in a peculiar shape 

 by means of wooden pegs, or folded into leaves like a book, 

 or simply dried without any care. The best isinglass is gen- 

 erally that which is rolled up and called staple ; the next best 

 kind is the book isinglass ; there are inferior kinds, which are 

 chiefly used for no other purpose than to adulterate the better 

 kinds. 



Isinglass of good quality is dry, whitish, semi-pellucid, and 

 inodorous. One hundred grains of it should afford ninety- 

 eight of matter soluble in water, which is gelatine and albumen, 

 and scarcely two parts of solid, insoluble matter, which consists 

 chiefly of phosphate of soda and phosphate of lime. It also 

 contains osmazome, according to the analysis of Mr. E. Solly. 

 M. Thenard has given this name to an extractive matter, con- 

 tained in muscular flesh and in the blood of animals, which 

 he considers of a peculiar nature. It has an agreeable smell 

 and taste, and is found in bouillons of meat in the proportion 

 of one part to seven of gelatine. Vanquelin discovered it in 

 some fungi. It is the substance which gives the flavor of 

 meat to soups, and hence its name, from 6^, smell, and fapos, 

 soup. 



The same objections apply to isinglass as to gelatine as a 

 therapeutical agent, and it is surprising that, while this gela- 

 tine is expunged from the last edition of the London Pharma- 

 copeia, that of hartshorn is suffered to remain. It was for- 

 merly regarded as an antacrid, lubricating, and incrassating 



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