3. The wheel watch maintained a record of all 

 tuna schools, bird flocks, and scattered 

 birds and mammals sighted. 



4. Synoptic weather observations, made daily 

 at 0000, 0600, 1200, and 1800 GCT, are 

 summarized in table 3. In addition, certain 

 standard weather observations accompanied 

 all BT lowerings. 



Scientists' log 



USWB Form 12 10F (original at U. S. Weather 

 Bureau Records Center, Asheville, N. C.) 

 EDO depth recorder charts 

 Barograph records 

 Tuna morphometric sheets - short form 



HUGH M. SMITH CRUISE 27 



Seven storms with winds of moderate 

 gale force (28 knots) or greater were en- 

 countered. They varied induration from 

 less than 6 hours to over 72 hours. The 

 most violent occurred on October 25 at ap- 

 proximately 45°N. , 172°E., when the ba- 

 rometer dropped to 986.5 mb. and the winds 

 reached a velocity of 68 knots. The storm 

 tracks during the months of the cruise are 

 shown in figures 44 to 46. 



5. The EDO depth sounder failed completely on 

 September 30, so bottom profiles were ob- 

 tained of only the southern part of the section 

 along 160°W. longitude. While the instru- 

 ment was functioning, some excellent re- 

 cordings were made of the evening rise of 

 the deep-scattering layers to the surface. 



6. On November 3, 1954, about 6 hours were 

 spent ashore on Laysan Island, which is a 

 part of the Hawaiian National Wildlife Refuge. 

 Only a few scattered Laysan albatross and 

 small numbers of blackfooted albatross, 

 Laysan finch, shearwater, terns, and one 

 flock of about 50 young frigate birds were 

 sighted on the island. There were no signs 

 of nesting at this time. The Hawaiian monk 

 seal population was estimated to be between 

 100 and 150. 



Form and Location of Field Data 



The following records were kept on Charles 

 H. Gilbert cruise 17; they are on file at POFI 

 except as otherwise noted: 



Original oceanographic data, Log Sheet "A" 

 Bathythermograph Log Sheet "B" (duplicates 



at Scripps Institution of Oceanography) 

 Chemical data sheets 



BT slides (Scripps Institution of Oceanography) 

 Thermograph records 

 Track charts 

 Deck log 

 Occurrence of tuna schools, birds, and 



aquatic mammals 

 Plankton log 



Flowmeter and sampler calibration log 

 Standardized surface trolling data sheets 



Itinerary 



The Smith departed from Pearl Harbor on 

 January 5, 1955. Engine trouble developed on 

 January 19 at 32 "30^. , 170°30'E. The vessel 

 put into Midway Islands for repairs, arriving on 

 January 24 and departing Midway on January 31. 

 About 12 hours were spent on February 10 sur- 

 veying the wildfowl refuge at Laysan Island. The 

 vessel returned to PearlHarbor on February21, 

 1955. The cruise track and station positions are 

 shown in figure 47. 



Primary Missions 



1. Forty-nine oceanographic stations were 

 occupied at the positions indicated on figure 

 47. Casts with 13 bottles were made on all 

 stations to approximately 1,200 m. The 

 bottle intervals in the upper 200 meters were 

 determined from the vertical temperature 

 structure indicated by the bathythermogram 

 taken at the station. Each bottle carried two 

 protected reversing thermometers and 

 bottles 5, 7, 9, 11, and 13 also carried an 

 unprotected thermometer. 



2. Salinity samples were drawn from each 

 Nansen bottle and returned to the POFI lab- 

 oratory for analysis. In addition, at every 

 second BT between 32°30'N. , 170 o 30'E. and 

 Midway Islands, surface samples were taken. 

 The salinity of the station samples is given 

 in the station data (table 4) and at the BT's 

 in the last column of the BT data, table 5. 

 The salinity profiles are presented in figures 

 78 to 82 and the distribution at the surface 

 and on the 25.2, 26.0, and 26.8 sigma-t 

 surfaces in figures 83 to 86. 



3. Dissolved oxygen analyses using the Winkler 

 method were made aboard ship on samples 

 from each depth. The observed values are 

 given in table 4, the profiles in figures 87 

 to 91, and the distribution on the 25.2, 26.0, 

 and 26. 8 sigma-t surfaces in figures 92 to 94. 



4. Inorganic phosphate analyses were also made 

 aboard ship on samples from each depth at 

 all stations. Additional surface samples 



