AQUATIC PKODUCTS IN ARTS AND INDUSTIIIES. 227 



OIL FROM LIVERS OF SHARKS AND RELATED SPECIES. 



The livers of various species of sharks and allied fish are suitable 

 for oil-production, j^iving rise in some localities to important fisheries. 

 Tlie principal species used are the sleeper shark, otherwise known as 

 the nurse, ground, or gurry shark {Somniosus) , taken in northern 

 waters from the Arctic seas southward to Massachusetts, Oregon, and 

 France; the basking or bone shark {Cetorhinus), formerly quite 

 numerous, but now taken to a less extent, north of Europe and on the 

 coast of Peru, Australia, California, etc.; the oil shark [Galeorlii- 

 nus), on the Pacific coast, especially in California, and the dog-fish 

 {Squahis), distributed throughout both hemispheres. In addition to 

 these, nearly every species of shark yields livers suitable for oil- 

 rendering. 



The sleeper shark appears to be the most important species so far 

 as oil-making is concerned. This is a large fish, individuals ranging in 

 length from 12 to 25 feet. The livers yield from 12 to 50 gallons of 

 oil each when taken in the autumn, but in the spring and summer 

 they are almost worthless for oil purposes. On the New England 

 coast this species is much less numerous than formerly, but it is 

 reported in abundance on the Pacific coast of the United States. 



During the autumn the taking of the sleeper shark is a somewhat 

 important branch of the minor Icelandic fisheries, and it is also taken 

 b}^ the Russians off the Kola Peninsula. The most important fisherj^, 

 however, is off the coast of Norway', and especially between Lofoden 

 Islands and Bear Island, in depths of from 150 to 200 fathoms of 

 water. The Norwegians employ small vessels of 20 to 35 tons, carry- 

 ing about six men each, the season beginning the first of October and 

 ending in February. The fish are taken by means of large, strong- 

 hooks baited with fish or salted seal blubber. 



The basking shark, probabl}^ the largest of all sea fishes, has been 

 taken very extensively for the oil contained in the livers, but owing 

 to decrease of the species the quantity now secured is much reduced. 

 This fish attains an enormous size, the prevailing length of fully- 

 grown individuals being 30 to 35 feet. The liver is proportionally 

 large, yielding ordinarily from 80 to 200 gallons of oil and occasionally 

 as much as 400 gallons. Indeed, a yield of (100 gallons has been re- 

 ported from a single individual, but this has not been satisfactorily 

 established. This species differs from other sharks in not being 

 voracious. Therefore it must be taken with harpoons rather than 

 with baited hooks. There is said to have been quite an extensive 

 fishery for it on the Massachusetts coast about the middle of the 

 eighteenth centur3^ According to Captain Atwood, writing in 1880, 

 "Not more than half a dozen have been caught near Provincetown 

 since 1810." 



The basking shark is numerous on tlie coast of Peru and Ecuador, 



