y 4 principles which must govern the developments of the:future! are not difficult to oT comprehend, and it is satisfying intellectually to have some basis for appraising in terms of probability the random estimates which have been presented to the public. Some of those estimates, it must be said, though emanating from distin- guished scientists, are not marked by the scientific discipline which is so rigorously observed in the laboratory. passionate, Certainly they cannot be regarded as dis- It might therefore be profitable for us to examine briefly (a) the relation of increase in power to increase of descructive capacity, and (b) the several factors which must determine the inherent power of the bomb. As we have seen, the radius of destruction of a bomb increases only as the third root of the explosive energy released. Thus, if Bomb A has a radius of total destruction of one mile, it would take a bomb of 15000 times the power (Bomb 5) to have a radius of destruction of ten miles.“ In terms of area destroyed the proportion does not look so bad; nevertheless the area destroyed by Bomb B would be only 100 times as great as that destroyed by Bomb A. In other words, the ratio of destructive efficiency to energy released would be only one-tenth as great in Bomb B as it is in Bomb A. But when we consider also the fact that the area covered by Bomb 5 is bound to include to a much greater degree than Bomb A sections of no appreciable military significance (assuming both bombs are perfectly aimed), the military efficiency of the bomb falls off even more rapidly with increasing power of the individual unit than is indicated above \hat this means is that even if itwere | technically feasible to accomplish it, an increase in the power of the bomb 43. Since the Hiroshima bom: had a radius of total destruction of sometning under 1-1/l miles; its power would have to be increased by some 600 tines to gain the ppPothotscat ten mile radius. The bomt of longer destructive radius would of course not have to be ained as accurately for any given target; and this fact may prove of importance in very long range rocket fire, which can never be expected to be as accurate as bombing from airplanes, But here again, large numbers of missiles will also make up for the inaccuracy of the individual missile, i