ing The results obtained at the farther stations are tabulated below, Station 7 Ailinginae Eniwetok Wake Johnston Approximate largest Wave Range (mi.) Height (cm) 40 200 500 1.9 6.2 3* 1500 Period No. of (sec) Wavea 375 350 320 3 5 7 Undetectable above high background * Results by TWX subject to later correction In addition, two or three very long period (85 minute) waves about 1 cm high were observed on the Cherokee record from Eniwetok, where the background was very low. Microbarographic records were obtained at both Wake and Johnston Islanis. The water wave arrivals reported above are much larger than those reported during CASTLE. This increase is attributed to the actotl of ten increase in sensitivity of the present instrument over that used for CASTLE. It is significant that Ailinginae at 40 miles range received smaller waves than Eniwetok (200 miles), This result agrees with the microbarograph records analyzed for CASTLE, in which the "shadow zone" for net integrated air pressure impulse was shown to extend at least 30 miles from the shot. It also indicates that these long waves are generated by barometric in-~ pulses and not by energy directly transmitted to the water. The wave generation process seems to be independent of the source conditions (surface or air burst). COPIED/D0; ; Lan Rt 0% Y Q