21664741911 Encyclopædia Britannica, Volume 27 — VaselineBoverton Redwood

VASELINE, or mineral jelly, the Paraffinum molle of the British Pharmacopoeia, a commercial product of petroleum which is largely employed in pharmacy, both alone and as a vehicle for the external application of medicinal agents, especially when local action rather than absorption is desired, and as a protective coating for metallic surfaces. “Vaseline” is a registered proprietary name (coined from the German Wasser, water, the Greek ἔλαιον, oil, and the termination -ine), and is strictly applicable only to the material manufactured by one company (the Chesebrough Manufacturing Company), but it is commonly applied in a generic sense. As met with in commerce, vaseline is a semi-solid mixture of hydrocarbons, having a melting-point usually ranging from a little below to a few degrees above 100° F. It is colourless, or of a pale yellow colour, translucent, fluorescent, amorphous and devoid of taste and smell. It does not oxidize on exposure to the air, and is not readily acted on by chemical reagents. It is soluble, in chloroform, benzene, carbon bisulphide and oil of turpentine. It also dissolves in warm ether and in hot alcohol, but separates from the latter in flakes on cooling.

The process employed by the Chesebrough Manufacturing Company in the manufacture of vaseline is said to consist essentially in the careful distillation of selected crude petroleum, vacuum-stills being used to minimize dissociation, and filtration of the residue through granular animal charcoal. The filters are either steam-jacketed, or are placed in rooms heated to 120° F., or higher. The first runnings from the filters are colourless, and when they become coloured to a certain extent they are collected for use as a lubricant under the name of “filtered cylinder oil.”

(B. R.)