ACIPENSER HUSO. 131 



those called book and ordinary staple are made of the intestines, 

 and probably of the peritoneum, of the fish. The sounds which 

 yield the finer isinglass consist of parallel fibres, and are easily rent 

 longitudinally ; but the ordinary sorts are found composed of 

 double membranes, whose fibres cross each other obliquely, re- 

 sembling the coats of a bladder. 



" Isinglass receives its shape in the following manner : the 

 sounds are taken from the fish while it is fresh, slit open, well 

 washed, divested of every thin membrane which envelopes the 

 sound, and then exposed to stiffen a little in the air. In this 

 state they are formed into rolls, about the thickness of a finger, 

 and in length according to the intended size of the staple ; a thin 

 membrane is generally selected for the centre of the roll, round 

 which the rest are folded alternately, and about half an inch of 

 each extremity of the roll is turned inwards. Having thus settled 

 the proper dimentions, the two ends of what is called the short 

 staple are pinned together with a small wooden peg ; the middle 

 of the roll is then pressed a little downwards, which gives it the 

 resemblance of a heart, and thus it is laid on boards, or hung up in 

 the air to dry. The sounds which compose the long staple are 

 larger than the former, but the middle part of the roll is bent more 

 considerably downwards, and, in order to preserve the shape of the 

 three obtuse angles thus formed, a piece of round stick is fastened 

 in each angle with small wooden pegs, in the same manner as the 

 ends. It this state it is permitted to dry long enough to retain 

 its form, when the pegs and sticks are taken out, and the drying 

 completed. Lastly, the pieces of isinglass are joined together in 

 rows, by running packthread through the peg holes, for the con- 

 venience of package and exportation. 



" The membranes of the book sort being thick and refractory 

 will not admit of the same formation, and therefore the pieces, 

 after their sides are folded inwardly, are bent in the centre, in 

 such manner that the opposite sides resemble the cover of a book, 

 whence its name ; a peg, run across the middle, fastens the sides 

 together, and thus it is dried like the former. The cake isinglass 

 is formed of the bits and fragments of the staple sorts, put into a 



