THE SEA FISHERIES OF EASTERN NORTH AMERICA. 147 
It was first brought to notice at the Centennial Exhibition, and re- 
ceived the high commendations of the jury on the fisheries and foods. 
The fish are first thoroughly cleaned and washed, and then immersed in 
boiling water for a short time for the purpose of removing the skin. 
They are then subjected to a subsequent treatment by which 3 pounds 
of extract are obtained from each barrel of menhaden, or 4 pounds if 
the entire fish is manipulated without separation from the bones. This 
process does not in any way affect the value of the fish for the produc- 
tion of oil or manure, and therefore constitutes an important utilization 
of a waste product, the proceeds of which will probably in time much 
more than pay all the increased cost of treatment. 
The same method can be applied to other fishes of sufficient size to 
warrant their evisceration, although it is hardly likely that any fish but 
the menhaden can be profitably treated in this manner, being actually 
shipped to Italy for the purpose of adulterating the genuine olive oil. 
There are other modes of preserving animal substances, especially fish, 
in use in various parts of the country, but those already given are the 
most important. 
In addition to the consumption of the flesh of fish as food, other parts 
of the body are used for a similar purpose, the most important being 
the livers and the air-bladders. The livers of many fish, especially 
the Gadidd@, of some of the sharks and some other species, furnish oil in 
very great quantity ; and those of the cod especially, and other fish of 
- the cod family generally, are used as food, particularly as nutriment for 
invalids affected by consumption or other wasting disease. The oilis 
also used for industrial purposes, which will be referred to hereafter. 
The air-bladders or sounds of fish are very extensively employed in 
the preparation of so-called isinglass, of which the most esteemed is 
that from the sturgeon and the hake. 
Of late years an excellent glue is made from the skin as well as the 
air-bladder of fishes, but this has mostly technical applications. The 
isinglass of fish when used as food is usually employed for the most part 
in the preparation of jellies, gum-drops, &c., as well as in the refining 
of beer and other beverages. 
Under the head of the application of fish as food must be ineluded 
their use as bait for the fisheries, as also their destruction by their fel- 
lows for their sustenance. These subjects will be referred to here- 
after. 
Besides the use of the meat of the fish, either fresh, salted, dried, 
smoked, pickled, spiced, in oil, &c., there are certain portions of the 
body which are considered more or less delicacies. Among these the 
heads of many species are preferred to the rest of the body. The boiled 
head and shoulders of the cod, the striped bass, and some other species 
are considered especially excellent, as are the fins of the halibut. In- 
deed, in the earlier history of the country the head and fins only of the 
halibut were utilized, the rest being thrown away. ‘The tongues and 
