AQUATIC PRODUCTS IN ARTS AND INDUSTRIES. 211 



tioTi aud adoption of cheaper substitutes for the relatively high-priced 

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

 employed in the fisliery, 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 nuirketcd principally in St. Johns, Glasgow, London, and 

 Leitli; those from the waters north of Europe, at Dundee, Copen- 

 hagen, Hamburg, and Archangel, and that from the Caspian seal fish- 

 eries at Astrakliaii. 



Seal oils vary in specific gravity fnmi O.iJlo to 0.030 at 59° F. 

 According to Brannt, they are composed principallj^ of glycerides of 

 physetoleic 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 all)uminous 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, quickly 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 comj)ound 

 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, chiefly seal oil, or rather seal-oil foots, and small quantities 

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

 and loM' specific gravity of the shark oil imparting the special quali- 

 ties to this com i30und. Swedish " three crowns " oil is a compound 

 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 very 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 usuallj^ 

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

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

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



SKA-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 pi-evious to 1803, but the first vessel specially fitted out for 



