Thermal Gaseous Diffusion Diffusion Method Through Barriers 3 Centrifugal 1

INTRODUCTION Fig. I i'only one of the various possible systematic arrangements of the elements that occur in nature, or have recently been produced. The elements are arranged i n order o f increasing atornir number. indicated by the fignre immediately below the sytnbol of each element. Nuclear physiriqts th ink of tlie atornic number Z as the runnber of positively charpcl particles. called protons, contained in the core or nueleas of an atom of a given elernen t. T HE familiar saving "a little knowledge is a dangerous thing" is partirularly apropoc in the rase of atomic energy. Following President Truman's announcemen t of the bornhina; of Hirosliirtia on August 6. 1945, the air was filled with radio reports. Virtually every newspaper and magazine in the country followed with feature articles o n atomic power. These are continuing and. in addition. we are heirla; exposed to a plague of books on the subject. In the sweep of publicity. the facts have often been ignored or hidden beneath a flood of over-enthusiastic extrapolation and speculation. \ -serond important number in the periodic table is the atomic weight. listed just above the chemical symbol. Thr syrnhol 4 will he used for atomic weight. On this scale the 1 igh test and simplest of elements, hydrogen, has an atomic weight of 1.0080. As Z = I, hydrogen must contain only one proton in its nucleus. The single electror~ that svvirls ahout this nucleus has a weight of only about 0.0005 units. Thus hydrogen nuclei are the charged particles. protons, that constitute building blocks in all nuclei. and the relative weight of each of these elementary particles before incorporation in such nuclei is 1.0075. i.e.. slightly greater than I. It seems particularly tirnelv that an accurate evaluation he made of the present and future rornpetition to petroleum of this new source of energy.