There are, in India, two distinct forms of the native oil mill. One of these is used alternately as an oil or sugar mill ; the other, of which there are some modifications, is a mortar with revolving pestle, and is of wood or stone—generally granite. Two oxen are harnessed to the gearing, which depends from the upper end of the pestle ; a man sits on the top of the mortar, and throws in the seeds that may have got displaced. Tho mill grinds twice a day, a fresh man and team being employed on each occasion. When sesammu oil is to be made, about seventy seers measure,. or two and a half bushels, of seeds are thrown in ; to this ten seers, or two quarts and three-quarters of water, are gradually added ; this, on the con tinuance of the grinding, which lasts in all six hours, unites with the fibrous portion of the seed, and forms a cake, which, when removed, leaves the oil clean and pure at the bottom of the mortar. From this it is taken out by a cocoanut-shell cup, on the pestle being withdrawn. Many seed oils are made almost entirely in the above way.
The oil mills at Bombay, Surat, Cambay, Kur achee, etc., have a very strong wooden frame round the month of the mortar ; on this the man who keeps the seeds in order sits. In Sind a camel is employed to drive the mill instead of bullocks. Castor-oil seed is thrown into the mill like other seeds, as already, described; when removed, the oil requires to be boiled for an hour, and then strained through a cloth, to free it of the fragments of the seed.
Castor-oil, made from either the small or large varieties of the Ricinus, is an exception. This is first parched in pots containing something more than a seer each. It is then beaten in a mortar and forMed into balls ; of these, from four to six teen seers are put in an earthenware pot, and boiled with an equal quantity of water for the space of five hours, frequent care being taken to stir the mixture to prevent it from burning. The
oil now floats on the surface, and is skimmed off pure.
The cocoanut palm nut is first stripped of its husk, which furnishes the substance from which coir and its rope is made, the shell is broken, and the copra, or fatty lining enclosing the milk, is taken out. Three maunds, or ninety pounds of copra, are thrown into the mill with about three gallons (eleven eutcha seers) of water, and from this is produced three maunds, or seven and three quarter gallons of oil. Copra, in its unprepared state, is sold slightly dried in the markets ; it is burned in iron cribs or grates on the tops of poles, as torches in processions, and as a means of illumination for work performed in the open air at night. In 1878-79, 325,408 cwt. of oil-cake, value Rs. 9,95,648, was exported from India. In the year 1882 -83, the export of oil-seeds from India was 643,184 tons, value Rs. 7,07,12,013 ; and oils to the value of Rs. 41,62,766. Mr. Edward Loarer's processes for making his veget able wax, by solidifying castor-oil by sulphuric acid, would admit of that oil being exported in a convenient form. By one process the solidify ing cost Rs. 41, and by a cheaper process only R. 1-11-3 per ton, and the acid is got rid of by remelting.—Balfour in Madras Museum Records; Do., Commercial Products ; Eng. Cyc. ; Simmonds; Roxb. ; Voigt ; O'Sh. ; Cat. Exhib., 1851, 1862; Powell ; Low's Sarawak ; Indian Field ; Madras Ex. Jur. Rep. by Drs. Cleghorn, Scott, and Hunter, and Lt. H. P. Hawkes; Smith's Chin. Mat. Med. ; Mr. E. Loarer on Vegetable Wax.