These peculiar shapes might probably be introduced originally with a view to conceal and disguise the real substance of isinglass, and preserve the monopoly ; but, as the mask is now taken off, it can not be doubted to answer every purpose more effectually in its native state, with out any subsequent manufacture what ever, especially to the principal consum ers, who hence will be enabled to procure sufficient supply from the British colonies. Until this laudable end can be fully ac complished, and as a species of isinglass, more easily produceable from the marine fisheries, may probably be more imme diately encouraged, it may be manufac tured as follows. The sounds of cod and lin& bear great analogy with those of the accipenser genus of Linmeus and Artedi; and are in general so well known as to require no particular description. The Newfoundland and Iceland fishermen split open the fish as soon as taken, and throw the back bones, with the sounds annexed, in a heap ; but previously to incipient putrefaction, the sounds are cut out, washed from their slimes, and salted for use. In cutting out the sounds, the inter costal parts are left behind, which are much the best ; the Iceland fishermen are so sensible of this, that they beat the bone upon a block with a thick stick, till the pockets, as they term them, come out easily, and thus preserve the sound en tire. If the sounds have been cured with
salt, that must be dissolved by steeping them in water before they are prepared for isinglass ; the fresh sound must then be laid upon a block of wood, whose sur face is a little elliptical, to the end of which a small hair-brush is nailed, and with a saw knife the membranes on each side of the sound must be scraped off. The knife is rubbed upon the brush oc casionally, to clear its teeth ; the pockets are cut open with scissars, and perfectly cleansed of the mucous matter with a coarse cloth ; the sounds are afterwards washed a few minutes in lime-water, in order to absorb their oily principle, and lastly in clear water. They are then laid upon nets to dry, but if intended to re semble the foreign isinglass, the sound of the cod will only admit of that called book, but those of ling both shapes. The thicker the sounds are the better the isinglass.