Show messages by liblit luo acre were described as an almost interception proof means of communication during warfare by dr phillips thomas ri research search engineer of an indianapolis electric company the method would would be especially effective in comman communication 1 between the ground an and d planes in the air he pointed out asserting a message could be intercepted only by cutting into the beam directed at the plane other electrical developments demonstrated were a lamp which he explained would destroy all germs in a given confined area such as a hospital operating room and and a black light which produces various colors |