IT has continually been urged in these columns that an organised endeavour should be made to link up scientific knowledge with appropriate action in social, economic, and national affairs. Sir Alfred Ewing's presidential address to the British Association at York indicated the extent to which scientific workers are now concerned with the social consequences of their discoveries. At the present moment the disorganisation in the world's economic and distribution system, with the resultant widespread industrial depression and unemployment which has resulted from the advent of power production, is perhaps uppermost in our minds. The dangers which threaten civilisation through its failure to make a rightful use of the enormously increased productive powers with which mechanical science has endowed it, are by no means the only threat which the gap between scientific advance and moral or ethical development offers. The fourteen years which have passed since the War have, as yet, brought no check to the prostitution of scientific effort to destructive purposes. Far more destructive weapons are now available, and a repetition of the calamity of 1914 may well threaten the extinction of civilisation. As yet, however, neither scientific workers nor any other section of the community has succeeded in calling any real halt in armaments, or in inducing the Governments of the world to base their policies upon the obvious fact that the renunciation of war as an instrument of national policy is a fundamental condition of the security of civilisation.