VOL. 9, NO. 3
DETECTION OF STRONTIUM
523
Auto of future to demand better lubricants. Automobiles will soan have such great speed and acceleration that special extreme-pressure lubricants not now available to the public will be needed to keep their transmission and differential gears from scoring and breaking down under the strain to which they will be put. This is the suggestion of H. C. Mougey and J. 0 . Ahnen, engineers of the General Motors Corporation, made recently before the American Petroleum Institute meeting in Chicago. They pointed out that even now the generally accepted theory of lubrication does not bold for some parts of the automobile. It is widely thought that in lubrication a film of oil actually prevents rubbing surfaces from coming together, the engineers said. But, they declared, this condition does not apply to highly loaded gears which make contact a t fast rubbing speeds as in the transmission and differential of an automobile. Pressures between automobile gear teeth are often as great as 400.000 pounds per square inch while well-lubricated bearing loads rarely exceed 2000 pounds per square inch. "With these conditions prevailing it is not difficult to imagine that we are fast apuroachina stated. "The fact that - the limit of caoacitv . . of ordinary oils," the engineers . we are not now in difficulty can probably be attributed to the intermittent nature of the loading .which nermits time for temperature equalization between periods of load."Science Service
