footy f : i/, i fi [| he pr hoy ll it oa with Victorcen thimble" ionization chambers which had been previously calibrated, The saturation behavior of the chambers was studied and at the operating voltage of 900 volts the chambers were well onto the plateau. The current collected at 900 volts was in excess of 95 per cent of that collected at 5,000 volts. } At the low and intermediate radiation intensity ranges the sources con~ sisted of radium and a several-curie Co°® source, For the high intensity region a one~Mev industrial x-ray machine was employed, By comparing the response to the collimated and uncollimated beams of the x-ray machine it was possible to deduce the solid angle over which the chamber was responsive. As stated above in the section on the electrometer, at four-hour inter~ vals the sensitivity of the electrometer was, checked, igbis was done by introducing standard currents of 107°, 107°, and 107°” amperes into the electrometer in place of the ion chamber current. The range of sensitivity of the equipment was from 5 mr/hr to,5 kr/hr. Each time the instruments were serviced in the field a 25-mc Coo? source was used to check the over-= all operation of the system. 8 RESULTS The distribution of off-atoll measuring locations in a southerly semicircle about Eniwetok was chosen because the prevailing winds at higher altitudes at the pertinent time of year were considered to be northerly. The perveraity of nature revealed itself on shot day as the upper air motion was predominantly toward the north, Accordingly, none of the fall-out waa carried over the measuring sites off-atoll. No radiation, within the detect- ability of the instruments, was indicated at any of the off~atoll sites. There are plotted on Figure 6 the gamma-ray intensity versus time data for those islands on Eniwetok where data were obtained: Engebi, Runit, Bijiri, Aniyaanii, ard Rigili. Parry and Eniwetok suffered no fall-out within the limits of detectability of the equipment. Complete data around Eniwetok Atoll were not obtained because the ionization chambers located on Bogallua, Ruchi and Bogon islands were destroyed by blast and thermal damage. Landline telemetering from Engebi to Parry was installed but did not survive the shot. The only significant results from the King shot were the Slowex data which have been incorporated into the Project 5.2 report. (See report WT634, ) 9 CONCLUSION Although the lack of conclusive results from this experiment is in no way a reflection on the operation of the equipment but rather on an unfortunate distribution of measuring sites, the participants in this experiment would not recommend duplicating the equipment for any future experiments of this type.