86 REPORT OF COMMISSIONER OF FISH AND FISHERIES. 



the " poud," (36 pounds.) The kind called "summer-caviar," however, 

 sells at from 6 to 9 "roubles," ($4.20 to $0.30 gold.) 



The milt of the " belouga"( Acipenser huso) aud of the common stur- 

 geon (Acipenser Guldenstadtii) is left from three to four days in the 

 brine, and then shipped in barrels. The milt of a"belouga" of medium 

 size often weighs 27 pounds, and that of the common sturgeon 12 pounds. 



The roe of the "lestche," (Abraniis brama,) of the " soudak," (Lucio- 

 perca sandra,) and of the " vobla," (Leuciscus rutilus, L.,) is also used for 

 making a kind of caviar which is chiefly sent to Constantinople and to 

 Greece. Greek merchants come to Astrachan, buy the roe of these fish 

 at the " vatagas " (fishing-establishments,) and there prepare the caviar 

 themselves. They draw from the body of the fish the little bags which 

 contain the roe, throw them together promiscuously, and cover each 

 layer with a certain quantity of salt. They then press the whole be- 

 tween boards weighted down by heavy stones. This caviar remains thus 

 for a month, after which the Greeks put it in casks aud ship it. Caviar 

 which has been thus prepared is cut in slices shaped like disks, and is 

 much sought after in Greece. 



Manufacture of isinglass. — The bladder of fish, which is known in 

 trade by the name of "feuille d'esturgeon" in French, "Hauseublase" in 

 German, and "isinglass" in English, is extracted from the inner side 

 of the swimming-bladder, not only of the " belouga," but also of other 

 kinds of sturgeon, as likewise of the Silurus glanis and of the Cyprinus 

 carpio. It is true that the large sturgeon yields the greatest quantity of 

 bladder, but the best is that of the common sturgeon, (Acipenser Gulden- 

 stddlii,) while the most inferior quality is that which comes from the 

 Silurus. Good isinglass must be pure, white, shining, half- transparent, 

 dry, and horny, without taste, but not without some perfume. Good 

 fish-bladder dissolves in water heated to 30 or 40 degrees Eeaumur 

 (about 100 to 122 degrees Fahrenheit) without leaving any residue, and 

 when it grows cold it becomes a transparent aud almost colorless gelatine. 



The fish-bladder is mostly prepared by young boys, superintended by 

 experienced laborers. First, the swimming bladder of the fish is thrown 

 into the water, where it is left for several days ; the water being fre- 

 quently changed, in order to detach all the fatty aud bloody particles 

 from the bladder. The hotter the water the quicker is this done. The 

 bladders are then taken out, and cut lengthwise into strips, which are 

 exposed to the sun and air. These strips, or leaves, are usually spread 

 out, in order to dry them, with their outer side on small boards of 

 lindenwood ; the inner side is formed by leaves [lamellae) of pure 

 isinglass, which, after having been well dried, are carefully detached 

 from the outer side. The leaves of isinglass thus obtained are laid 

 between pieces of linen, to preserve them from the flies and from dust; 

 then they are placed under a press, so that they may not become 

 warped, but may form smooth cakes. It is only after all these different 

 operations have been performed that the laborer proceeds to pick the 



