INTRODUCTION. 
XXV11 
manufacture. “ The ‘ maws 5 are roughly circular, two or three inches in diameter, and somewhat 
resembling a bad muffin. 55 
The Polynemus Indicus (p. 60) is also another of the isinglass producing fish, and is known 
under the name of {Kora, Mai.) at Calicut. “ Its maws are shaped somewhat like the blade of a 
trowel, and from seven to eight inches in length, by two or three in width : they are not obtained 
in nearly so large quantities as those of the Yeta.” 
There are other species of fish, as the Lates calcarifer; Lobotes surinamensis; some species 
of Scicena, &c. from which isinglass could be procured, but perhaps the small quantity which they 
yield, and the trouble it would entail in procuring and preparing it, render them little used in 
Malabar for this purpose. 
The “ fish maws 55 of Indian commerce are the swimming bladder or sounds extracted from 
the fish and dried in the sun. McClelland gives the following as the Bengal process:—“The 
sounds when received fresh are opened and stripped of the vascular covering and internal mem¬ 
brane, washed, and at once made up into any form the manufacturer finds most convenient for 
packing. 55 If dry before receiving it, it is steeped in water and the same process adopted. 
For the removal of discoloured parts and softening the more solid without dissolving the thinner, 
they are steeped a short time in alum water (consisting of alum 1 ounce to 4 or 5 gallons of water), 
when saturated they are removed, spread on a linen or cotton cloth that has been saturated with 
the same solution, then rolled up lightly and set aside for twelve hours, this is repeated till 
they are bleached. It should be observed, bleaching neither improves the quality nor increases the 
value of the article. 
The Indian isinglass is said, (by Dr. Royle on Isinglass, at page 74) to be “ essentially good, 
“ and its defects such as are easily susceptible of improvement by increased attention to the pre¬ 
paration, so as to remove the present (1849) objection ; and in fact some specimens (from India) 
“ being better prepared than others, proves that there can be no difficulty in preparing them all 
“ equally well. 55 . . . “ Its objectionable properties consist of its still retaining something of 
“ the fishy smell as well as being in part insoluble, apparently from some portion of the albuminous 
“ membranes still continuing adherent to the purer gelatinous parts. It is probable that by increased 
“care in cleaning and drying, by exposure to air, some of these defects may be removed.’ 5 (p. 37.) 
Its thickness might be decreased by stripping off more of the outer membranes, and also by 
beating and pressing between slabs and rollers. Bengal isinglass appears more fibrous, because the 
middle and not the inner coat is used (but this is not a proof that the inner coat of the Polynemus 
Indicus is the best), instead of being torn into shreds by the hand it might be rasped or cut, for 
if in shreds doubts arise as to its genuineness, whilst it cannot be cut in India so evenly as is done 
in Europe by machinery, therefore sending it home in sheets is the best. It should be prepared 
when the fish is fresh, and under a light roof, because the action of the sun may melt any oily 
particles, and diffuse them through the membraneous structure. Oiliness and smell may perhaps 
