of the Labrador continental shelf it was necessary for the first and 

 only time during the 1953 operations, to heave to because of boisterous 

 weather. After a delay of approximately 18 hours progress was 

 resumed. A coastal belt of ice off Cape Farewell, combined with 

 darkness and low visibility forced the termination of the section, the 

 last of 22 stations being completed 14^ miles off Cape Farewell late 

 on the evening of 20 July. The Evergreen then proceeded via Argentia 

 to Woods Hole where the field work for 1953 was concluded with the 

 unloading on 27 July of oceanographic equipment and personnel. 



The oceanographic work was under the supervision of Oceanogra- 

 pher Floyd M, Soule who was assisted by LCDR Armand J. Bush and 

 LT John E. Murray. Other assistants in the observational work 

 were Francis N. Brown, yeoman first class; Lewis M. Lawday, aerog- 

 rapher's mate second class; Hugh R. McCartney, Jr., aerographer's 

 mate second class; Donald Zacher, aerographer's mate third class; 

 and Joseph R. Stefanick, seaman. 



Of the 306 stations occupied during the season and postseason 

 cruises, the 22 stations comprising the section across the Labrador 

 Sea were occupied from the surface to as near bottom as was practi- 

 cable, and at the remaining 284 stations the observations extended to 

 a depth of about 1,500 meters where the depth of water permitted. 

 As in previous years the intended depths of observation, in meters, 

 were 0, 25, 50, 75, 100, 150, 200, 300, 400, 600, 800, 1,000, and thence 

 by 500-meter intervals. The dynamic heights have been referred to 

 the 1,000-decibar surface, except for the section across the Labrador 

 Sea where the 1,500-decibar surface was used as the reference surface. 



In addition to the usual measurements of temperature and salinity, 

 261 samples were taken during the occupation of the South Wolf 

 Island-Cape Farewell section for ultimate determination of total 

 phosphorus concentration. 



Temperatures were measured with deep sea reversing thermometers. 

 Most of the protected thermometers were of Richter and Wiese 

 manufacture but a small percentage were manufactured by Negretti 

 and Zambia, G. M. Manufacturing Co., and the Kahl Scientific 

 Instrument Corp. The depths of observation were based on unpro- 

 tected thermometers made by Richter and Wiese and by Kahl. The 

 thermometers were used in pairs and a program of intercomparison 

 of protected thermometers was carried out by periodically changing 

 the individual thermometers comprising the pairs. In all 2,042 

 comparisons were made. After eliminating constant corrections 

 these comparisons gave a probable difference between the corrected 

 readings of a pair of thermometers of 0.011° C. As many of the 

 thermometers had recent laboratory comparisons with thermometers 

 tested by the National Bureau of Standards, and as in most cases the 

 temperatures are the means of the corrected readings of a pair of 

 thermometers, it is considered that the observed temperatures listed 



47 



