220 REPORT OF COMMISSlOJ^iER OF FISH AND FISHERIES. 



but wlien they are very lean, as was the case in 189G, for instance, 

 from 36 to 56 are required for 1 gallon of oil. In that fisliery the liv- 

 ers are fatter at the beginning than at the end of the season. They 

 average about 55 pounds to the 100 fish; but during the years when 

 they are unusually lean it is much less, as in 1883, when the average 

 weight of 100 livers was only 12|^ pounds. Usually at the Lofoden 

 Islands 250 to 1,100 cod give 1 barrel of livers, and 2 barrels of livers 

 yield 1 barrel of oil; but in 1883 from 700 to 1,100 fish were required 

 for 1 barrel of livers, and 4 or 5 barrels of those were necessary for 1 

 barrel of oil. Aside from the benefits accruing from the fatness of 

 tlie livers, anything gained in quantity is always lost in quality in the 

 preparation of medicinal oil. 



While it is somewhat difficult to distinguish among the oils made 

 from the livers of the various members of the cod family, yet ordina- 

 rily there are certain distinctive characteristics apparent to the skilled 

 oil-refiner. Cod oil is of a greenish j^ellow color and usuallj' has less 

 pressings or foots than any of the others. Hake oil is almost white, 

 but that made from hake taken on certain grounds has a pinkish 

 color, which may be removed by filtration through a mineral earth. 

 Pollock oil is distinguished by a slightly bitter taste and has a faint 

 reddish cast. Its weather-test is rather lower than that of cod oil, 

 especially when it has been slightly overcooked in the rendering. 



Oil extracted from perfectly fresh cod livers is light and odorless, 

 and, owing to its extensive use in medicine, is known as medicinal cod 

 oil or ' ' cod-liver oil. " According to the extent of decomposition of the 

 material before the extraction of the oil, the color ranges through all 

 shades of yellow and brown to very dark brown, this color being 

 attributed to the decomposition of the hepatic tissues and fluids. 

 These dark oils are of two general grades; one, the brown, which is 

 inferior to the light-brown or medicinal oil, but is frequently used for 

 such ; and the other, the dark-brown or curriers' oil, is the f)Oorest 

 grade prepared, and is exclusively used for technical purposes. Prob- 

 ably it would be better to say that there are two principal varieties of 

 oil, the medicinal and the curriers', and that unusual market condi- 

 tions may result sometimes in the employment of the poorest of the 

 medicinal oil for technical uses or the best of the curriers' oil for 

 officinal i^urposes. 



The medicinal value of cod-liver oil was known centuries ago among 

 the Laplanders in northern Europe, the descendants of the Norsemen 

 in Iceland, and the Eskimos in Alaska. The use of the oil gradually 

 extended in Europe during the eighteenth century, being a popular 

 home remedy among many seacoast communities and used empiri- 

 cally by phj'sicians. Percival and Bardsley in 1782 recommended its 

 use in cases of gout and chronic rheumatism. In 1841, J. Hughes 

 Bennett, of Edinburgh, published a pamphlet on its medicinal quali- 

 ties, strongly recommending it in many cases, and this had much to 



