
The SciencesMarch 1, 1962
Ultrahigh Vacuum
In 1950 the limit of man-made vacuum appeared to be a pressure equivalent to 108 millimeter of mercury. A breakthrough in technique now provides pressures four orders of magnitude lower

Ultrahigh Vacuum
In 1950 the limit of man-made vacuum appeared to be a pressure equivalent to 108 millimeter of mercury. A breakthrough in technique now provides pressures four orders of magnitude lower