July 19, 1961 - Capt. Virgil I. Grissom spent four hours atop a Redstone missile today, ready for a ride into space that was blocked by an abrupt build-up of tropical clouds. It was to have been the nation's second manned spaceflight - virtually a duplicate of the 302-mile suborbital flight made by Comdr. Alan B. Shepard Jr. on May 5. Today was the second time weather forced a postponement. The firing was tentatively rescheduled for 6 a.m. EST Friday. Observers noted one new item of attire not worn by Commander Shepard. This was a five-inch parabolic mirror on Capt. Grissom's chest. It was to reflect the instrument panel and enable the capsule camera to record not only the astronaut's movements but also simultaneous readings on the instrument dials.