DISCOVERY INVESTIGATIONS 

 STATION LIST 



1937-1939 

 Plates (IV-VI) 



INTRODUCTION 



THIS list is a continuation of the Station Lists already published in Discovery Reports, 

 vols. I, III, IV, XXI, XXII and xxiv, and it gives particulars of the observations made 

 by the R.R.S. ' Discovery II ' from October 1937 to May 1939. Its arrangement follows 

 that of the Station Lists published in vols, xxi, xxii and xxiv. 



Nutrient salt contents are expressed in milligram atoms of the particular element 

 per cubic metre of sea water. For pH estimation McClendon's standards were used; 

 a correction was made for the fading of the tubes as described in vol. xxi, and the 

 values represent the pH in situ corrected for temperature and salt error but not for 

 pressure. For the estimation of phosphate 2 ml. of ammonium molybdate were used 

 with a trace of copper and the resulting figures corrected for salt error by muhiplying 

 by a factor of 1-35. Silica was estimated by the method of Atkins and Cooper and no 

 correction applied for salt error. 



Depths measured by unprotected reversing thermometers are recorded in the column 

 headed 'Depth by thermometer'; those recorded in the column headed 'Depth 

 (metres)' were determined from the amount of wire paid out and from the most 

 probable slope of the wire found by interpolation between the thermometric measure- 

 ments; the small index figure placed above the figure for depth shows from which 

 hoist of water sample bottles the sample was obtained. Time is expressed in the 

 24-hour system ending with midnight (0000). The difference of the ship's time from 

 Greenwich mean time (GMT) is noted in the 'Remarks' column, this difference 

 holding good until another entry is made. Times in heavy type refer to biological 

 observations made between sunset and sunrise. 



The following symbols are used for nets, apparatus, etc. : 



B Oblique. 



BNR Russell's bottom tow-net. A i m. net on a rectangular frame attached to skids which 



raise it clear of the bottom. 



DC Conical dredge. Mouth 16 in. (405 cm.) diameter, with a canvas bag. 



DGP Pressure depth gauge: a modification of the Budenberg pattern. 



DLH Large dredge. Heavy pattern, 4 ft. (1-2 m.) long. 



H Horizontal. 



KT Kelvin sounding tube. 



NHP A modification of Harvey's phytoplankton net. A metal funnel (aperture 30-5 cm.) leads 

 to a recording mechanism and thence to a sleeve-shaped silk net of 200 meshes to the 

 linear inch, terminating in a conical bucket. The apparatus is hauled vertically at approxi- 

 mately 10 m. a minute, and the mechanism records the volume of water filtered. 



N 50 50 cm. silk tow-net. Mouth circular, 50 cm. (19-5 in.) diameter: 200 meshes to the 



linear inch. 



N 70 70 cm. tow-net. Mouth circular, 70 cm. (27-5 in.) diameter: mesh graded, at cod-end of 



silk with 74 meshes to the linear inch. 



N 100 I m. tow-net. Mouth circular, i m. (3-3 ft.) diameter: mesh graded, at cod-end of 

 stramin with 10-12 meshes to the linear inch. 



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