NAPHTHA, the most fluid bitumen, is nearly colorless, but of a yellowish tinge, transparent, and emits a peculiar odor. It swims on water, its specific gravity being from 011 to 0.84. It burns with a bluish-white flame and thick smoke, and leaves no residue. It con sists of carbon, 82'2, and hydrogen, 14.8; being the only fluid destitute of oxygen. It is found in Persia, in the peninsula of Apcheron, upon the western shore of the Caspian Sea, where it rises through a marly soil in the form of vapor, and, be ing made to flow through earthen tubes, is inflamed for the purpose of assisting in the preparation of food. It is collected by sinking pits several yards in depth, into which the naphtha flows. It is burned in lamps, by the Persians, instead of oil. Near the village of in the state of Parma, there exists a spring, which yields this substance in sufficient quantity to illuminate the city of Genoa, for which purpose it is employed. In a coal mine near Manchester, England, there is a spring of Naphtha, welling up between the seams, and which yields 150 gallons a day.
On the surface of Seneca Lake, New York, a large quantity of naphtha, or " rock oil," floats at particular periods of the year. This Seneca rock oil is de rived from the bitumen escaping out of the shales which are very carbonaceous in the middle counties of western New York. The shale beds dip south and a
little west under the waters of the lake, and where the opening of the seams meets the water at the bottom of the lake the bitumen oozes out, and rises to the surface. There are many other localities on this continent, where native naphtha or bitumen is found. It is found abund antly in Kentucky. Any highly fossili ferous shale, which is dark colored from the large quantity of vegetable matter contained in it, and which also contains pyrites disseminated throughout, gene rally affords naphtha. Native naphtha boils at 201° F.
Artifleial Naphtha is obtained by the distillation of the crude coal-tar, one of the residues of the manufacture of coal gas. It has a specific gravity of •857, and consists of carbon, 88.04; hydrogen, 12.81; oxygen, Dr. Ure gives the boiling point as 316° ; but this must have been a very impure naphtha. The chief and valuable agent in coal naphtha is Benzoic (which see), which is obtained by distilling the coal-oil at a temperature not exceeding 185°. Coal naphtha is a valuable solvent for many solid hydro carbons, as gutta percha and ceoutchouc and when pure contains no oxygen. On this latter account it is the only substance suitable for preserving potassium and the other easily oxidized metals.