The generalized pattern of circulation and hydrology given above In Its 

 broader aspects Is definitely lacking In detail, but many existing questions may 

 be answered when results are published from recent cruises and from scheduled 

 International Indian Ocean Expedition cruises. 



II. DATA COLLECTION 



Standard oceanographic station procedure as practiced by the U.S. Naval 

 Oceanographic Office Oceanographers (H . O. Pub. No. 607, 1955), was 

 carried out at each of the 30 stations occupied. A volunteer team of four 

 Coast Guard enlisted men directed by Chief Quartermaster Davis, USN, 

 collected the samples and assisted In some of the laboratory work. Paired 

 reversing thermometers were attached to Nansen bottles, and bottles were 

 placed at all Intermediate standard depths. Dissolved oxygen was determined 

 by the unmodified Winkler method on board ship. Salinity samples were sealed 

 in citrate bottles and returned to theOceanographIc Laboratory of the U.S. 

 Naval Oceanographic Office. Deteimlnation of salinity was made with a 

 University of Washington type salinometer. Depths at which observations 

 were actually made were determined by thermometric calculation from readings 

 of protected and unprotected thermometers. Accuracy of observations Is con- 

 sidered to be to. 02° C. for temperature, 10.05 parts per thousand {%) for 

 salinity, and i0.05 milliliters per liter for dissolved oxygen. Percentage of 

 saturation of dissolved oxygen was interpolated from Fox's Tables (Fox, 1907). 

 When light permitted, transparency was determined with a 30 cm . white 

 SecchI disc . Meteorological information was obtained every 3 hours by aero- 

 graphers assigned to the Icebreaker. Continuous underway soundings were made 

 by a UQN-IB echo sounder. 



