Science: Vacuum Ecstasy

Dr. Kenneth Claude Devereux Hickman is a suave, sociable British chemist who works for the Eastman Kodak laboratories in Rochester. N. Y. His specialty is the efficient recovery of vitamins from fish oils by a clever technique of distillation.

Distilling vitamins requires a very high vacuum. Scientists do not expect to make a perfect vacuum, any more than they expect to reach the cold of absolute zero, but they try to get as close to perfection as possible.

Mechanical pumps have a certain limit beyond which they cannot decrease the vacuum chamber pressure any further. So Dr. Hickman has designed a sort of chemical pump which goes to work after the mechanical pump has done its best. A spray of oil vapor is shot in one side of the chamber, out the other. Some of the gas molecules roaming inside are struck by the oil particles, adhere to them, are thus escorted outside through the oil vapor exit.

The Electrical Journal, a Westinghouse publication, last week said: “This new pump is marvelously effective. It reduces the number of gas molecules to the point where they can almost literally be counted.

Although this still is many thousands in a small space it is low enough—as compared with previous evacuations—for a laboratory man to become ecstatic.” The pressure obtained is equivalent to one hundred-millionth of a millimetre of mercury, which is not far from one hundred-billionth of atmospheric pressure.

High vacuums are essential not only to the distillation of vitamins but also in the manufacture of thermos bottles, radio tubes, X-ray apparatus, electric lamps.

They are also a potent research tool in many branches of science.