. X -50- ' Single bomb; but after some forty years or more of its use, the largest anount of it povred into a single lip was about six tons 46 To be sure, greater power in the bomb will no doubt be attained by increasing the efficiency of the explosion without necessarily adding to the quantities of fissionable materials used. Put the curve of progress in this direction is boune te flatten out and to remain far short of 100 per cent. The bomb is, to be sure, in its "infancy," but that statement is misleading if it implies that we may expect the kind of progress which we have witnessed over the past century in the steau engine, The bomb is new, but the people who developed it were able te avail thenselves of the fabulously elaborate and advanced technology already Any now device created today is_already at birth a highly perfected instrunont. an Oe, fo é One cannot disiiss the matter of in “ mies existing. wig cfficiency of the bomb without noting. that the military uses of radio-activity may not be confined to bombs, Even if the project to produce the bomb had ultimatcly failed, theo by-products forned from sone of the intermediate processes could have been used as an cxtremely vicious form of poison gas, It was estimated by two members of the "Manhattan District" project that the radioactive by-products forned in one day's run of a 100,000 kw, chain-reacting pile for the production of plutoniun (the production rate'at Hanford, Vashinzton was fron five to fifteen times as great) right be sufficient to nake a large arca uninhadoitabic. LT Fortunately, however, materials which ere dangerously radioactive tona to lose their radioactivity rather quickly and therefore cannot be stored. uo, In the 10-ten bob, of which it is fair to estimate that at least LO per cont of the weight must be attributed to the metal case. In armor-picrcing shells and bombs the proportion of weight devoted to metal is very much higher, running above the 95 per cent mark in major-caliber naval shells. 7. . Smyth Report, paragraphs 4.26-28.