open sea (Fig. 8). Preparations for the Field: Preliminary planning coordi- nated by the Division of Biology and Medicine and by Joint Task Force 7, specified that the survey vessel, the WALTON (DE 361), should report to Eniwetok on or about June 5 and that she should be available for the cruise for approximately ten days after June 10. The WALTON reported on schedule at Eniwetok, and was joined immediately thereafter by members of the survey party, who began the supervision of the installation of survey equipment. Survey Equipment: The equipment used in collecting plank- ton, sampling water, and continuous monitoring of surface water, was installed on the afterdeck of the WALTON, approximately above the port screw. The counters, a recorder, and chemistry laboratory facilities were placed below decks in the after officers' quarters and in a crew's berthing compartment. Spe- cifically, the major items of equipment were: 1. A continuous surface water monitoring probe with tank and water connections (Fig. 1), a unit designed and constructed by the HASL. 2. A power winch (Fig 2), feeding 3/16 inch steel cable over an A-frame and davit, for the use of plankton nets (Fig. 3) and water sampling bottles (Fig. 4). 3. A steel platform (Pig. 4) extending two feet over the port side of the ship to provide space for work with nets and water sampling bottles. 4. A temporary chemistry laboratory set up on sheet ply; . é + i ly he