Production of Isinglass on the Coasts of India. 103 



and delivered over to the Isinglass and to the Caviare makers. 

 The fresh Sounds are first split open and well washed, to se- 

 parate the blood and any adhering extraneous matter, (on the Lake 

 Baikal, warm water is used, according to Georgi), they are then 

 spread out, and exposed to the air to dry, with the inner silvery 

 white membrane turned upwards. This, which is nearly pure Gela- 

 tine, is carefully strip t off, laid in damp clothes (or left in the outer 

 covering), and forcibly kneaded with the hands. It is then taken out 

 of the cloths, dried in the form of Leaf Isinglass, or rolled up, and 

 drawn in a serpentine manner into the form of a heart, horse-shoe 

 or lyre (long and short Staple), between three pegs, on a board 

 covered with them ; where they are fixed in their places by wooden 

 skewers. When they are somewhat dried thus, they are hung on 

 lines in the shade till their moisture is entirely dissipated. The ob- 

 long pieces are sometimes folded in the form of Book Isinglass. In 

 order to obtain good Isinglass, it is necessary to have well-arranged 

 rooms to dry it in, as at Astrakhan. 



It has been questioned by some authors whether any Isinglass is 

 prepared with the aid of heat or of solution, but such will come 

 rather under the head of Gelatine, or of Fish-glue, than of Isinglass. 

 There is no doubt, according to Pallas even, that at the lower parts 

 of the Volga, a fine Gelatine is boiled out of the fresh swimming- 

 bladder, and then poured into all kinds of forms. In Gurief, a fine 

 boiled Fish-glue is prepared, perfectly transparent, having the colour 

 of amber, which is cast into slabs and plates. The Ostiaks also boil 

 their Fish-glue in a kettle. The Common Cake Isinglass is formed 

 of the fragments of the other sorts : these are put into a flat metallic 

 pan, with a very little water, and heated just enough to make 

 the parts cohere like a pancake, when it is dried. The Sounds of 

 Silurus Glanis and Barbel are pounded and boiled ; but, as the glue 

 does not entirely dissolve, the liquid is strained to separate the fila- 

 ments from the gelatine. Besides these, the cartilaginous and 

 tendinous parts of several fishes are boiled down to form Fish-glue. 



The Osseter yields the best kind of Isinglass ; that of the Beluga 

 is the worst obtained from the tribe of Sturgeons, but this is said to 

 be improved by the addition of that of the Sevruga and Sterlet. 

 The Glue of the last is the most tenacious, and is valued for inlaid 



