0018933 from Shot Yellowwood did not develop to the extent predicted, and launching signals were sent only to the launchers on Mary and Sally at H # 13-1/2 minutes, All rockets launched successfully, The rockets on Wilma were intentionally not launched, because it was apparent that their trajectories would not intersect the cloud, seen to have missed the cloud. Even of those fired, four were Three nose cones were recovered, The czp on the first nose cone was still intact, probably due to a short in the circuit that fired the nose cap removal squib; therefore, no s2mple was collected. The second nose cone was froma rocket programmed to open at 30,000 feet. of water. When recovered, the nose cone contained abcut 60 ml, At H / 9 hours the filter of this nose cone read about 1 mr./hbre at the surface, The third nose cone was from a rocket programmed to open at 55,000 feet, About 100 ml, of water had leaked into it, and the surface reading of its filter was 25 mr./bhr atH #9-1/2 hours, After this shot, an intensive effort was made to determine the c2use of leakage of water into the nose cones, It was found that the ball joint sezling the forward end of the nose cons efter sampling could beunce back 2 small zmount after closure, thereby permitting water to enter, <A Istching mechanism was designed to lock the ball joint in its totally clcsed position. This modification was then zepplied to all nose cones,