Show important 11 discovery new york jan 10 nikola testa announces that he has bas perfected macum tubes of such high illumination power that they may be used in lighthouses a and that they will enable phot ogra ahers to work by night an a well as day the results which mr telsa lias has attained has been ed b by ly the us of hi his vacuum tubes and his oscillator ahe light which he is able to produce by this means laas is as bright as that of the noonday sun dy by its me use every line of the object photographed may be made to stand out clearly and distinctly |