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Show SUM What |: Is Vacuum? THE traffic policeman did not hold up his hand and control the automobiles and wagons and people there would be collisions, confusion, and but little progress MMMM mL MLL in any direction. His business is to direct. The physicist who tries to obtain a vacuum that is nearly perfect has a problem somewhat like that of the traffic policeman. Air is composed of molecules— billions and billions of them flying about in all directions and often colliding. The physicist’s pump is designed to make the molecules travel in one direction—out through the exhaust. The molecules are much too small to be seen even with a microscope, but the pump jogs them along and at least starts them in the right direction. A perfect vacuum would be one in which there is not a single free molecule. For over forty years scientists have been trying to pump and jog and herd more molecules out of vessels. There are still in the best vacuum obtainable more molecules per cubic centimeter than there are people in the world, in other words, about two billion. Whenever a new jogging device is invented, it becomes possible to eject a few million more molecules. The Research Laboratories of the General Electric Company have spent years in trying to drive more and more molecules of air from containers. The chief purpose has been to study the effects obtained, as, for example, the boiling away of metals in a vacuum. This investigation of high vacua had unexpected results. It became possible to make better X-ray tubes—-better because the X-rays could be controlled; to make the electron tubes now so essential in long- range wireless communication more efficient and trustworthy; and to develop an entirely new type of incandescent lamp, one which is filled with a gas and which gives more light than any of the older lamps. No one can foretell what will be the outcome of research in pure science. New knowledge, new ideas inevitably are gained. And sooner or later this new knowledge, these new ideas find a practical application. For this reason tories of the General the primary purpose Electric Company of the Research is the broadening Labora- of human lectric TY Schenectady, N. Y. CM NUNIU MTU LU LEM LL REP PN PTR LSE PTE AVM CLM 95-376-A |