The filter discs were placed in 3-drain 

 shell vials which were stored in a desiccator in 

 the dark. At about 10 -day intervals the vials 

 were transferred to a can that was then sealed 

 with waterproof tape and placed in a freezer. 

 The filters were kept frozen and not exposed to 

 light until they were returned to the laboratory 

 for processing. 



Oceanographic Observations 



A bathythermograph lowering was made 

 immediately before each station and the re- 

 sulting temperature -depth record was used to 

 determine the spacing of the 6 bottles between 

 the surface and 300 meters. The deeper 7 

 bottles were placed at standard depths. Paired, 

 protected reversing thermometers were used 

 with each bottle, and, in addition, an unprotected 

 reversing thermonneter was used with the fifth, 

 seventh, ninth, eleventh, and thirteenth bottles. 



At each of the oceanographic stations 

 occupied along UO'-W. , lECW. , and MO'W. 

 longitude during the westbound passage (fig. 1), 

 13 Najisen bottles were used in casts designed 

 to reach 1,200 meters. However. Successive 

 losses of wire and persistently large wire angles 

 resulted in the casts frequently reaching depths 

 of less than 1,200 meters. Whenever practicable, 

 the large angles were reduced prior to release 

 of the messenger by steaming up on the wire. 

 In figure 6 the wire angle prior to steaming is 

 shown for each station. Also, the reduction in 

 angle prior to releasing the messenger is 

 indicated. 



A salinity sample was drawn from each 

 Nansen bottle and returned to the laboratory at 

 Honolulu for analysis. Samples were also 

 drawn for dissolved oxygen and inorganic phos- 

 phate determinations. All oxygen analyses were 

 run on board the Smith using a modified Winkler 

 method. The concentration of inorganic phos- 

 phate at all depths sampled was photometrically 

 determined on board from station 64 (HI) to sta- 

 tion 75 (H8). During this latter station, the 

 Automatic Servo -Operated Photometer (ASOP) 

 broke down. Subsequently, samples from 3 to 

 5 depths at each oceanographic station and sur- 

 face samples at zooplankton and C-14 stations 

 were frozen for analysis at the Honolulu 

 laboratory. 



"T" 



"T" 



> 1 10° W LONGITUDE 



I 120° W LONGITUDE 



I40°W LONGITUDE 



The thermograph was inoperative between 

 Honolulu and Manzanlllo, Mexico. A new ther- 

 nnal assembly, installed prior to departure from 

 Mexico, provided a continuous record of surface 

 temperature during the cruise back to Honolulu. 

 This record was particularly valuable in regions 

 of sudden change in temperature, such as at the 

 front near 4''N. latitude, 120°W. longitude. 



A temperature -depth plot was maintained 

 throughout the cruise using the uncorrected BT 

 records. A record of the BT observations, to- 

 gether with accompanying weather observations 

 and associated surface salinity and inorganic 

 phosphate data, are given in table 8. 



Meteorological Observations 



Figure 6. --Variations in wire angles w^ith 

 latitude, for the oceanographic stations 

 along 110°W., 120''W., and 140°W. 

 longitude. The solid symbol denotes the 

 angle prior to steaming up on the wire; 

 the open symbol the angle at messenger 

 time. The two angles for a particular 

 stationare connected by a vertical arrow. 



Standard marine weather observations, 

 recorded on USWB Form 1210F, were made 

 four times daily, encoded, and transmitted 

 whenever possible to San Francisco; data from 

 these observations are tabulated in table 12. The 

 meteorological observations acconnpanying each 

 of the oceanographic stations are included in the 

 heading for each station, table 7. 



A 



