~ Several dosimeters vere included to read the total exposure. One Gosineter was activated at 55 seconds after the detonation to give an estinate of the effects pf residual radiation. At 60 seconds, a solenclé- release mechanism caused the entire instrument to drop dowm the 8-iaech steel-pipe stations to 6 feet below the surface. Thus, the instruments _ were shiblded from most of the residual rediation. The device was housed ip en aluximum eanister 32" high and 7-1/2" in @iameter, with a 0.10-inch wall thickness. ‘The battery pack that povered the mechanienm was in the bottom half of the canister. A 6-inch space at the top of the canister was utilized for the placement of various ether dosincters, and Project 2.51 gold and sulphur neutron detectors for Shots Sumi end Cherokee. fhe instrument was activated “© Woon the melting of an cutectic elenent bythermel radiation. The eutectic element consists of two pieces of 0,008-inchbrassshim stock, rhated black with Ebenol ¢ and soldered with Cerroley 136, an eutectic that maltese at 136°F. ‘the total activation delay from tine of detonation is estimated st 1/2 second. 2.2.7 wou se act Mechenieal Brop Mechanisn. A mechanical Grep mechanism vas installed in the pipe caps of some ef the 4-inch and B-inch steel-pipe stations. These stations were instrumented with five sects of dosimeters. Three sets were suspended in the top of the station, and fell to the votten when activated. The first set of dosincters was suspended by a Black nylon string extending from an aru attached to the cap top through a hole in the cap. The gasmea data indicated that the string burned through in about 1/2 second after the detonation. A second set of dosi- fers > ATOMIC ENERGY ACTTOF 1954 36