HEADLIGHT OIL.
Alden, Iowa.
Please give the composition and properties of “headlight oil,” such as is used by the railroad companies in lanterns and headlights.
P. M. Edwards.
Answer.—Strictly speaking, headlight oil of the first quality is what its discoverer, Joshua Merrill, named mineral sperm. It is an illuminating oil intermediate between kerosene and neutral lubricating oil, the specific gravity of kerosene being .804, that of mineral sperm .847, and that of lubricating oil .883. The boiling points of these are respectively, 350 deg. Fahr., 425 deg., and 575 deg. It is volatile only at very high temperature, therefore, and cannot be ignited at less than 300 deg. Fahr., which is one reason why it is preferred to kerosene, particularly on railroad cars and locomotives and ocean steamers. The headlight oils in common use do not conform strictly to the above descriptions, being, some of them, only a fine quality of kerosene. The chemical constituents of refined petroleum are hydrogen and carbon, in the proportions of 75 of the former to 85 of the latter. We have not the precise chemical formula for headlight oil.
UNITED STATES NATIONAL CEMETERIES.
Bucyrus, Ohio.
How many United States National cemeteries are there, and where are they? What salaries are paid to superintendents? Are they kept in good condition?