conclusions that can be drawn are as follows: 1. The basic biast pattern trom nuclear explosions now appears to be established on quite firm theoretical and empirical grounds, in a self-consistent theory beginning with the growth of the fireball and extending to pressures less than 1 psi. 2. Atmospheric inhomogeneities markedly affect the blast variables at great distances for large-yield weapons. In particular, under normal temperature-lapse-rate conditions the peak pressures at great distances are markedly reduced. 3. Blast hydrodynamicsoffers considerable immediate promise as a diagnostic tool on tests of atomic weapons. The following isolated facts of interest have resulted from preliminary inspection of the data: 1. Water-surface displacement was 2 to 4 ft at Runit Island and 1 to 3 ft at Parry Island for Mike Shot. The waves produced by this shot were in general much smaller than predicted, being approximately one-tenth of those expected within the lagoon and nonexistent in the open sea. 2. A newly devised light and inexpensive deep-sea mooring, whichutilizes the top of undersea mountains rising to some 5000 ft under the surface, was proved highly successful. This ability to establish semirigid reference points in mid-ocean may well offer a valuable contribution to ocean studies in general. 3. The B-36D horizontal tail bending moment was approximately 62 per cent of design limit, although in the wing the bending moments due to gust were very low. At shock arrival this aircraft was approximately 24 nautical miles from bomb zero at an altitude of 40,000 ft. The preliminary conclusion implied is that the B-36D will not be capable of delivering a megaton bomb without an aid (drone or drogue) of one type or another. t 4. Identical peak pressures of 0.36 psi were measured on Parry Island for Mike and King Shots. This anomaly appears to be due to a refraction effect. 2.1 PROGRAM 7, LONG-RANGE DETECTION Program 7 was designed to aid in the development of, and obtain calibration data for, specialized equipment and techniques for the detection (and analysis, to whatever degree is feasible) of a nuclear explosion at great distances. The techniques utilized were extremely diverse in nature, covering the fields of electromagnetic radiation transport, air-borne lowfrequency sound, seismic-wave propagation, and the detection of fireball light, as well as the tracking, collection, and analysis of air-borne bomb debris samples. The quantity and general characteristics of the data and samples collected in this program are indicative of a successful operation, but practically no data have been reduced and analyzed in detail at the time of writing. Existing cloud-cover and smoke observations make the bhangmeter results appear questionable; however,fiz.al conclusions must await film analysis. Communication difficulties lessened the effectiveness of the King Shot air-sampling operations, but the samples obtained are adequate for at least partial analysis. The Mike Shot air sampling was more successful. Most of the remote stations report reception of excellent signals in conjunction with Mike Shot. For King Shot no reports have yet been received from these stations, but no difficulty is anticipated. . 2.8 PROGRAM 8, THERMAL-RADIATION MEASUREMENTS The thermal radiation emitted by an atomic detonation represents still another subject for investigation. The projects of Program 8 were each designed to document a particular aspect of this phenomenon. Near the surface of the earth attempts were made to measurethe total thermal energy received as a function of distance from bomb zero, the time variation of the thermal intensity received, and the energy spectrum exhibited by this radiation. In conjunction 12