Amongst the smaller cetaceans, the porpoises—called also dolphins ("puffydunters" on the east coast of Scotland)—and grampuses yield an excellent oil, second only in value to that of regular oil whales; and to obtain it, large numbers are occasionally killed in the British seas. The price of sperm oil ranges from £80 to £95 per tun. and that of ordinary train oil from £40 to £45 per tun of 252 gallons. The imports and consumption of the various kinds of whale oil for the five years 1871 to 1875 were as follows: Tuns. Value.
1871.... 24,679 £1,087,734 1872 18,719 8;35,590 1873 17,886 766,927 1874 17,051 751,359 1875. . . 19,359 917,701 A large quantity of very valuable oil is obtained from seals; and the seal-fishery, as a means of obtaining oil, is only second in importance to that of the whale. It is carried on chiefly on the shores of Newfoundland, Greenland, and Labrador. Like the whales, the seals have a thick layer of blubber in which the oil is contained. See SEAL. The first draining from the blubber is of a fine, clear, pale straw-color; the next, yellow or tinged; and the last is brown or dark. The price ranges in our markets at about £35 to Edper tun for pale, £30 to £35 for yellow, and £23 to £30 for brown. The whale and the seal oils are nearly all used for burning in lamps, and for this purpose they are admirably adapted by their great illuminating power. They are also the best lubricants for machinery.
Of the true fish oils, that from the cod is first in importance, more especially since its medicinal properties were discovered. It is made only from the liver of the fish; and the attempt which was made to induce a popular belief that the so-called cod-liver oil was different from the ordinary cod oil of commerce, was simply a cheat; no difference exists, and the oil is obtained just as good from the oil merchant at a moderate price per gallon as from the empiric at an exorbitant price per pint. Indeed, the purer the oil can be got, the better his in a remedial point of view, notwithstanding the efforts made to convince the public that a certain color is better than any other.
Instead of the old and somewhat rude methods of preparing the oil (see COD-MVER 010, much more complete and efficient arrangements are now adopted. The livers, when taken from the fish, are all examined, washed in clean water, and placed in sieves to dry. Thence they are transfeited to pans heated with steam, and after being exposed to a gentle heat for about three-quarters of an hour, tire heat is discontinued; and when cold, the oil which has separated is skimmed off, and strained through flannel bags into ,tubs. Here certain impurities subside, and the clear oil is poured off from the dregs, and the contents of numerous tubs are transferred to galvanized iron cisterns, in which a further settlement takes place. The oil is now ready for the filters, which are made of the strong
cloth called moleskin, through which it is forced by atmospheric pressure into the store tanks, which are also of galvanized iron. Hence it is pumped into the casks for export, which are usually hogsheads, tierces, and barrels. The value of cod-liver oil is about £34 to £40 per ton. The imports vary much according to the success of the fishery; they have reached nearly 1000 tons per annum. Besides its consumption in lamps, and for medicinal purposes, cod oil is used in making some kinds of soap. Oil is occasionally made from the herring, but not in very great quantities; it, however, forms a commercial article. It is made from tire whole of the fish, the smell of which it retains to a very disagreeable extent.
The lightest of all the fixed oils is made from the liver of the common shark; it ranges from specific gravity 0.865 to 0.867. This, and the oil made from the livers of the common skate (Raja 1)018), the Thornback (R. &mita), and the white skate (Rldnobatus eernie Wax), are often substituted for the cod-liver oil used medicinally, but have not its valuable properties.
Under the nathe of lard oil. large quantities of the oleine of lard have been imported of late years from America. It is a secondary product, arising from the great manufac ture of lard stearine for candle-making which has arisen in that country. Lard oil is worth about £45 to £53 per ton, and is principally used as a lubricant for machinery.
The solid vegetable fixed oils which find a place in commerce are palm oil, cocpa-nut oil, kokum or vegetable tallow, and carapa or carap oil. The palm oil is an oil of a bright orange-yellow color and an agreeable violet odor; it is obtained from the not covering of the hard seeds of the oil-palm (q.v.). The fruits, when gathered, are shaken out of the clusters, and are laid in heaps in tire sun for a short time, after which the natives boil them slowly in water, when the oil separates and is skimmed off the surface, and carried in small quantities to the &pots of the traders, who transfer it to casks which are prepared to receive it on board the ships, The quantity thus collected is enormous. The imports into Britain alone for the live years 1871-1875 were as follows, in tons weight: (1871) 52,394; 50,395; (1873) 50,897; (1874) 53,333; (1875) 45,228. Previous to 1840, the chief use of palm oil was in making soap, but it was about that time found that the palmitine or fat acid of this oil was admirably adopted for the manu facture of candles (q.v.); and since then it has become of much greater importance.