ON THE ADULTERATION OF ISINGLASS. 237 
isinglass to protect themselves and the public against impo- 
sition, and to exonerate those who have not participated in 
this newly discovered branch of the system of adulteration 
which has become so general. With these views I under- 
took a few experiments, and although there has not yet 
been time to complete the investigation, I am induced to 
publish the results in the hope of their being practically 
useful. 
Of the several varieties of isinglass, which, in the unman- 
ufactured state, are imported into this country, that called 
Beluga leaf is most esteemed for dietetical use, and this, 
when prepared and cut, constitutes the best Russian isin- 
glass of the shops. There are inferior varieties of Russian 
isinglass, such as the Samovey, which, being much cheaper 
than the Beluga, may perhaps be sometimes mixed with it 
when cut, but as the jelly made from such deteriorated 
specimens would be proportionately weak, the admixture 
would be thus detected. 
Brazilian isinglass is a cheap kind, which is extensively 
used for fining beer and other similar purposes, and this is 
also prepared and cut, like Russian isinglass, and is no 
doubt sometimes mixed with the Russian. The Brazilian 
variety, however, is much less soluble in water than the 
best Russian, and the jelly obtained from it is inferior in 
consistence, in transparency, and in flavor. 
When these different kinds of isinglass have been sub- 
mitted to the processes of the manufacturer, in which they 
are picked and purified (especially the inferior kinds,) rolled 
into ribbons,a.nd subsequently cut, the prices at which they 
are sold, wholesale, vary from six shillings to seventeen 
shillings a pound. The modern introduction of machinery 
has enabled the manufacturer to prepare the isinglass in 
much thinner shreds than was formerly the case when it 
was pulled to pieces by the fingers or cut with the scissors. 
There are those, however, who still prefer to have it in the 
thicker pieces, in which state it is called hand cut. 
