The Isinglass of Commerce. 251 



West Indian Isinglass.— \JndGY this name the isinglass 

 obtained in British and French Guiana enters into com- 

 merce. It is the produce of one or two siluroid fishes. In 

 British Guiana it appears to be obtained from the gilbackre 

 or gilbagre {Silurus Parkerii), a fish very abundant in the 

 estuaries of the rivers of the colony. A small quantity of 

 this fish-glue, as it is termed, is now exported from thence. 



In French Guiana some attention has also been given 

 to the preparation of isinglass obtained from the machorian 

 (S27?/ra.r/if/u), which is especially employed in the clarifi- 

 cation of beer. Reduced into small shreds by the action 

 of a mechanical plane, it dissolves completely in cold 

 water, and is compared with Russian isinglass as two 

 to three. Its cheapness gives it also advantages over the 

 latter. 



North American Isinglass. — Cod-sounds, which are 

 brought in great quantities from Newfoundland, are nothing 

 more than the salted air-bladders of these fishes. The 

 Iceland fishermen, as well as those of America, prepare 

 isinglass of a very excellent quality from cod-sounds, 

 though they are not acquainted with the method of clarify- 

 ing it which the Russians practise in preparing that article 

 from the sound of the sturgeon. 



Ribbon isinglass is obtained from the air-bladder of 

 the common hake {Merlucius vulgaris), or probably from 

 the fish passing under the name of hake on the coasts 

 of America {Phycis chuss). The air-bladder is thrown 

 into water to macerate for a little while, and taken out 

 and pressed between two iron rollers, by which it is elon- 

 gated to the extent of half a yard and more. It is then 

 carefully dried, packed, and sent to market. 



In the manufacture of ribbon isinglass from fish-sounds 

 it is customary to place the softened and moist or 



