Trinity Balloon launched to protest against U.S nuclear test in the Nevada dessert, using a banner saying "Stop Nuclear Tests". GP visits the test site for footage and to do measurements on radioactivity. Photos: (1) Balloon practice at Livermore, Ca, (2) View of Mercury, gate to the NTS, (3) Lloyd Anderson, communication base near NTS, (4) GP crew protest near gate NTS as workers arrives. (5) Balloon pilot Gene Stilp, (6) Crew struggling to keep balloon on the ground. (7) Balloon, (8) Tethered at entrance to site, while buses carrying workers file by, (9) Pilot Gene Stilp tethered with banner.