AQUATIC PKODIJCTS IN ARTS AND INUUSTKIKS. 211 



lion and adoption of cheaper snbslitutes for the relatively hiuli-priced 

 seal oil. Every year shows a decrease in the number of vessels 

 employed in the fishery, and when a vessel is lost or sold it is rarelj^ 

 replaced. Comparatively little seal oil is imported into this country, 

 the quantity in some years amounting to less than 1,000 barrels. The 

 price in bond approximates 45 cents per gallon. The Newfoundland- 

 oils are marketed principally in St. Johns, Glasgow, London, and 

 T.eith; those from the waters north of Europe, at Dundee, Coi)en- 

 hagen, Hambui'g, and Archangel, and that from the Caspian seal fish- 

 eries at Astrakhan. 



Seal oils vary in specific gravity from 0.015 to O.'.KJO at 59° F. 

 According to Brannt, they are composed principally of glycerides of 

 l)h3^setoleic acid, of palmitic, stearic, and a small quantity of oleic 

 acid and traces of butyric acid, valerianic acid, etc. ■ They show a 

 slight acid reaction when fresh, the acidity increasing with age. 

 Instead of the albuminous substances present in vegetable oils, the 

 seal oils contain a small quantity of glue which can be precipitated 

 with tannin and metallic salts. Thej'^ are very slightly soluble in 

 alcohol, and require almost an equal volume for solution in ether. 

 Mixtures of equal volumes of nitric and sulphuric acids produce a 

 reddish color, quicklj^ changing to brown. The adulteration of seal 

 oils is detected principally by the incomplete saponification if resin 

 oil be the adulterant, and by the degree of solubility in alcohol if other 

 blubber oils are employed. 



In addition to the pure oils there are several well-known compound 

 seal oils on the markets, the best known being the "three crowns." 

 Greenland "three crowns" is a mixture of several varieties of blub- 

 ber oil, chief!}' seal oil, or rather seal-oil foots, and small quantities 

 of whale and walrus, combined with oil from shark livers, the fluidity 

 and low specific gravity of the shark oil imparting the special quali- 

 ties to this compound. Swedish " three crowns " oil is a comiwund 

 of various seal oils with herring oil. 



The principal use for seal oil is for burning in miners' lamps, and 

 it is also employed in currying and to a verj^ small extent for miscel- 

 laneous purposes, especially' fiber-dressing. About 2,500 barrels are 

 used annually as an illuminant in the light-houses in the British 

 North American provinces. Owing to its sluggish nature it is usually 

 improved by the addition of mineral colza. An excellent miners' lamp 

 oil is said to be composed of seal oil, 40 per cent; whale oil, 25 per 

 cent; lardine (0.980), 10 per cent, and mineral colza, 25 per cent. 



SEA-ELEPHANT OIL. 



The sea-elephant or elephant-seal has furnished a large quantity of 

 oil to the American markets during the last eighty years. The whalers 

 operating in the extreme South Atlantic, and also the fur-sealers sail- 

 ing to Falkland, South Georgia, and the coast of Patagonia, secured 

 odd lots previous to ISOo, but the first vessel specially fitted out for 



