order to meet these requirements, a wire telephone system will be provided. The number of stations required on each island has nat been firmed up as yet, and it is believed that the total number of instruments (80) assumed in the Reconnaissance Report (see Pages IV-109 to IV-111) is still reasonable although facilities on Bogallua are no longer required. A manual telephone system will be employed. The main switchboard will be located in the Administration building on Parry Island. Subswitchboards will be provided on Eniwetok, Japtan and each of the three experiment islands. Submarine telephone cable will be installed for trunking between these switch- boards. Two 16 pair cables will be used between Engebi, Biijiri-Rojoa, Runit, and Parry; three 16 pair cables will be used between Parry and Eniwetok; two 6 pair cables will be used to Japtan and to each of the new Photo Tower locations mentioned elsewhere ard one 6 pair cable will be provided to buoys in the lagoon at moorings adjacent to Parry, Eniwetok and each of the three experiment islands. Plate No. 2), shows these cables. One of the cables be- tween the various switchboards is a spare intended to provide continuity of service in the event of damage to one cable. A four-channel radio back-up system will be provided to supplement the submarine cable trunking for emergency use. A public address system will be provided on each experiment island to call personnel from the field to a telephone. CONTROL AND SIGNAL CABLES: Existing Control and Signal Cable Installed Submarine. There are exist- ing submarine control and signal cables which were installed on the floor of the lagoon in January, February, and March of 1948 for use in Operation Sandstone. Tests were made on these cables in October, 1948 and February, 199 to check the condition of these cables, Refer to Plate 50 of the Reconnaissance 256