THE STURGEON. 79 



Art of making isinglass. 



discovered, and the following account of it pub- 

 lished by Humphrey Jackson, Esq. in the Philo- 

 sophical Transactions. 



". All authors, who have hitherto delivered 

 processes for making isinglass, have greatly 

 mistaken both its constituent matter and pre- 

 paration. 



" In my first attempt to discover the constitu- 

 ent parts and manufacture of isinglass, relying 

 too much upon the authority of some"chemical 

 authors, whose veracity 1 had experienced in 

 many other instances, I found myself constantly 

 disappointed. Glue, not isinglass, was the result 

 of every process ; and although in the same view, 

 a journey to Russia proved fruitless, yet a steady 

 perseverance in the research proved not only suc- 

 cessful as to this object, but, in the pursuit, to 

 discover a resinous matter plentifully procurable 

 in the British fisheries, which has been found by 

 ample experience to answer similar purposes. 



" It is now no longer a secret that the lakes 

 and rivers in North America are stocked with 

 immense quantities of fish, said to be the same 

 species with those in Muscovy, and yielding the 

 finest isinglass; the fisheries whereof, under due 

 encouragement, would doubtless supply all Eu- 

 rope with this valuable article. 



" No artificial heat is necessary to the produc- 

 tion of isinglass; neither is the matter dissolved 

 for this purpose; for, as the continuity of its 

 fibres would be destroyed by solution, the mas* 



