ridge to station 3746 located at 66°50' N., 59°16' W. This longitudinal 

 section was interrupted at station 3715, located at 61°04' N., 55°36' W., 

 on the evening of the 19th to replenish supplies at Narsarssuak, Green- 

 land. 



Leaving Narsarssuak on the morning of the 23d the longitudinal section 

 was resumed at station 3716, located at 61°30' N., 55°44' W., on 24 July. 

 From this station another diversion was made in order to run a section 

 across the Labrador Current to Loks Land on the northern side of the 

 entrance to Frobisher Bay. This section was completed at station 3725 

 on the afternoon of the 26th and the longitudinal section resumed at sta- 

 tion 3726 at 62°09' N., 56°05' W., on the morning of the 27th. Another 

 diversion from the longitudinal section was made beginning at station 

 3727, at 62°28' N., 56°17' W., to run a section across the West Greenland 

 Current at Fyllas Bank near Godthaab, Greenland. This section was 

 completed at station 3736 on the evening of the 28th. The longitudinal 

 section was then resumed at station 3737 located at 63°04' N., 56°36' W., 

 on the morning of the 29th, and concluded at station 3746 on 31 July. 

 Beginning with station 3742 serious mechanical difficulties began to be 

 experienced with the sonic sounding equipment which finally became 

 beyond the capacity of the ship's force to repair about the same time that 

 considerations of time and supplies forced the abandonment of further 

 work and the Evergreen returned to port, reaching Argentia on 6 August 

 to replenish, and Woods Hole, Mass., on 9 August to discharge ocean- 

 ographic equipment . 



During this activity 24 stations were occupied during the April survey, 

 17 during the May survey, and 42 during the June survey. At these 83 

 stations and the 30 stations occupied in running the triangle north of the 

 Grand Banks on the post-season cruise the observations extended to about 

 1500 meters where the depth of water permitted, and the dynamic topog- 

 raphy was referred to the 1000-decibar surface. The remaining 58 

 stations occupied during the post-season cruise extended from the surface 

 to as near bottom as was practicable. At these stations the dynamic 

 topography was referred to the 1500-decibar surface. The intended 

 depths of observation were 0, 25, 50, 75, 100, 150, 200, 300, 400, 600, 800, 

 1,000 meters and thence by 500-meter intervals. Temperatures were 

 measured by deep-sea reversing thermometers, principally of Richter ct 

 Wiese manufacture but including some made by Negretti & Zambra as 

 well as G. & M. Manufacturing Co. During the late winter, prior to 

 the beginning of field work, most of the thermometers had been calibrated 

 l)y the W^oods Hole Oceanographic Institution. Used in pairs, the 

 thermometers were shifted periodically during the surveys so that most 

 of the thermometers were each compared with several other thermom- 

 eters. After applying the corrections resulting from the winter's calibra- 

 tion, the intercomparisons permitted the elimination of systematic 

 differences and indicated the probable error of the measurements. A 

 total of 1105 individual intercomparisons were made, giving a probable 



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