On thirteen other islands -- weapon towers, photo tower, instrumented structures, recorder building, and a great variety of instrumented facilities. In all 839 separate scientific test facilities were ultimately designed and constructed, DEVELOPMENT OF DESIGNS AND DRAWINGS Information and criteria for the development of design were received in many ways: by letter, by conference, by telephone, by rough sketches, and in some cases by drawings quite completely indicating requirements, Throughout the entire period of two years starting early in 1949, the representative of J-Division, and the Holmes & Narver Chief Engineer, were in frequent and almost continuous contact by phone calls almost every day and by meetings at Los Alamos or at Los Angeles almost every week, Upon receipt of information as to requirements, the Engineering Division prepared preliminary drawings showing physical dimensions and all information necessary to indicate the manner in which the Users' requirements would be fulfilled, Prints of the preliminary drawings were submitted to J-Division for approval, J-Division, at its discretion, submitted the preliminaries to the User; changes and suggestions made by J-Division and/or the User were then incorporated on the preliminary drawings and, if the changes were extensive, the drawings were resubmitted, The number of unscheduled preliminary drawings and the number of changes made on them was great, , After approval of preliminary drawings by J-~Division, working drawings were started. In the development of working drawings all design departments had a part -- architectural, civil, sanitary, structural, mechanical, and electrical. Even while working drawings were being prepared, changes were frequently made at the request of J-Division, This was not at all unexpected, since new ideas were being put into definite form and many ideas never used before were being applied on these drawings, Although the many changes were sometimes discouraging to the men preparing designs and drawings, it was recognized by all that they were pioneering and taking part in the development of a new and significant undertaking and that change meant progress, At the same time that drawings were being prepared for the many buildings and scientific stations, the location maps were also being developed, The exact location of each scientific station in relation to the weapon tower and in relation to the other stations was of great importance, Each station was plotted on one of 37 drawings which to- gether made up the overall location map, The orientation of the station, its distance and direction from the zero tower, and location (determined by coordinates) were all shown The location maps were continually changing because stantly being added and moved, and it was extremely times impossible to keep the location maps current, 5-12 its geographic for each station. stations were condifficult and at Therefore, in