Developments of the technique of separated oscillating fields and the atomic clock. Move to Harvard University from Columbia University and Brookhaven National Laboratory; work at Harvard concentrating on the first molecular beam magnetic resonance apparatus, doctoral thesis of Harwood Kolsky; Jerrold Zacharias and the cesium beam clock; Brookhaven Molecular Beam Conferences (beginning 1947), significant developments in resonance. Also prominently mentioned are: P. I. Dee, Harwood Kolsky, Polykarp Kusch, William Aaron Nierenberg, Pendulchron, Ken Smith, John Hasbrouck Van Vleck, Robert F. Vessot, Earl Wilkie; Brookhaven National Laboratory Molecular Beam Conferences, Fort Monmouth, Frequency Control Symposium, National Science Foundation (U.S.), United States Army Signal Corps, United States National Bureau of Standards, United States Office of Naval Research, and University of California at Berkeley.