400 A HISTORY OF FISHES 



privileged by the King." In parts of the Orient, notably in 

 China and the Philippine Islands, there is a considerable trade 

 in shark fins, which are used for making soup. After being cut 

 from the body, the fins are well salted or dusted with lime, and 

 then dried in the sun. The Japanese prepare a tasty dish from 

 the flesh of Sharks and Dog-fishes, which is known by the name 

 of "shark-flesh paste." 



In addition to providing man with food, most fishes yield a 

 number of by-products, which may be of some commercial 

 importance. Chief among these are the oils of various grades, 

 ranging from the crude oils used in certain manufacturing 

 processes to the medicinal cod-liver oil, so valuable in the 

 treatment of wasting diseases. In fishes like the Herring, 

 Sardine, Menhaden, Salmon, and Mackerel, the bulk of the 

 oil is found in the body, and furnishes what is known to the 

 trade as "fish-oil," a product used to a large extent in the 

 manufacture of paints. In the Cod and many other fishes, 

 the oil is contained mainly in the liver, and yields a product 

 which in the crude state is used by the tanning industry, being 

 particularly valuable in the manufacture of "chamois" leather, 

 for tempering steel, and in the preparation of lower-grade soaps, 

 while, after refining, it provides the well-known medicinal oil. 

 Norway alone produces nearly one and a half million gallons of 

 cod-liver oil annually, Iceland about half a million gallons, while 

 considerable quantities are produced by Canada, Newfound- 

 land, the United States, Great Britain, and Japan. 



Fish meals and fish fertilisers are products of some economic 

 importance, and succeed in using up all the waste parts of the 

 fish. The former is used to feed poultry, pigs, and cattle, and 

 is particularly reliable for chickens and young animals, as it 

 contains protein in a readily digestible form, as well as a high 

 percentage of calcium phosphate. It is of interest to note that 

 the Greek historian Herodotus, writing in about the fourth 

 century B.C., mentions a tribe living in pile-dwellings round 

 Lake Prasias that "feed their horses and other beasts on 

 fish, which abound in the lake in such a degree that a man 

 has only to open his trap-door, and let down a basket by a 

 rope into the water, and then wait a very short time, when he 

 draws it up quite full offish" (Rawlinson's translation). 



Fish glue is a product obtained mainly from such fishes as the 

 God, Haddock, Pollack, and Hake. Most of it is derived from 

 the skin of the fish, but waste glue and fish-head glue are also 

 manufactured. Isinglass is a pure gelatinous substance obtained 



