-14 that the general model of fallout set forth is consistent with the data and essentially correct. III. PLANS It is clear that the peoples of the world are ‘extremely interested in radioactive fallout because of the bearing that the new phenomenology of the nuclear age has on everyone's life. For this reason, we must understand radioactive fallout in all its intricacies. It is to be hoped that the study will be a cooperative, international one. The United Nations Scientific Committee on Effects of Atomic Radiation offers an ideal forum for the discussion and consideration of the problem. From these deliberations will come further suggestions, ideas, appraisals and statement of the problem. The methods developed in this country for measurement and all the data collected are available to everyone. It is our hope and intention that this problem, like others of the atomic age, will come to be generally understood. — Fallout is normally considered an aspect of atomic warfare and nuclear armament. There is somesimilarity, however, between the weapons fallout and the hazard from a reactor accident, in which radio- active products would be disseminated over a limited area, but never reach the stratosphere or undergo anything like the world-wide tropospheric dissemination. As it has sc often been observed in the past, so it is again true in this instance, that a new fact of nature is likely to have its beneficent as well as its somber and frightening aspects. As we learn about the way the world-wide fallout particle, probably as tiny as a virus molecule, wends its way from the stratosphere — through the tropopause into the troposphere and, within a few weeks, collides with a water droplet and thus is brought to the earth's surface by rain, we shall learn more about the circulation of the atmosphere, about the way in which rain is formed, and about the questions which will naturally arise more (more)