assembled and connected for filling operations. The entire cryogenics system was filled with liquid hydrogen in June 1952 with the use of Camco transport Dewars operating from Boulder. The results of this test indicated that certain modifications were necessary to the cryogenics system. These modifications were completed in July, and a second filling was made. This fill- ing proved that the system, as now designed, was adequate and could be duplicated overseas. At the Buffalo plant of American Car and Foundry, the Mike device was completely as- sembled, less the cryogenics system and , during the week of 14-19 July. Thisgave added experience in the assembly of the which is the most difficult part of the operation and, for the first time, all the components of the device except the cryogenics system were assembled. This Task Group assumed operational control of the Mike device on 25 July 1952. The Forward Area training conducted during the months of September and October by the Scientific Task Group included activities such as Dewarfilling, trial movements of the transport Dewars from Parryto the shot island aboard an LCU, radiological-safety monitor training, and electronics checksof the television equipment aboard the USS Estes, which was used as a firing control ship in addition to being the command ship. It is somewhat difficult to distinguish training activities from field tests, check-outs, and trial runs using the apparatus or equipment to be used in the actual test. These last-minute checks were the culmination of months of research, study, and training. They were not training activities in the sense that repetition was necessary to successful accomplishment, but they were proof tests of basic ideas, circuitry, and final calibrations. All training of TG 132.1 was culminated in the comprehensive rehearsals held in the For- ward Area to determine the state of readiness of all elements. The Mike Shot rehearsal, re- ferred to as the “MX rehearsal,” was held on 28 October and covered all phasesof the test: with the exception of those items which would cause undue interference with preparations for the actual shot. This rehearsal was successfully carried out, and no serious deficiencies were noted in TG 132.1 preparations. 3.5 - MOVEMENT TO THE FORWARD AREA AND ASSEMBLY OF SUBORDINATE UNITS 3.5.1 Personnel Information regarding the expected number of personnel to move to the Forward Area during Operation Ivy was obtained from the monthly status reports as submitted by the various staff sections, task units, programs, and projects. This information was graphically plotted and used by the interested staff sections and by Holmes and Narver (H&N)in planning for transportation, housing, messing, and administration in the Forward Area. Because of the many variables affecting the length of stay of the majority of personnel in the Forward Area, this expected-population graph was not entirely accurate but was useful for over-all planning purposes. The processing of individuals prior to movement overseas was accomplished by the Adjutant General at Los Alamos. This processing included: 1. Preparation of travel orders for each individual. 2. Preparation of identification cards for those persons not already possessing them. 3. Notifying each individual of the immunization requirements and the procedure for obtaining them. 4. Ensuring that each person, prior to movement to the Forward Area, had a valid radio- logical-safety physical examination. 5. Working in close liaison with the J-2 Section to determine the clearance status of the individual. (No orders were issued to those not considered good security risks.) 6. Issuance of necessary governmenttravel requests to military personnel for commer- 22