1915] Michacl,et al.: Hydrographic Records of ScripiJS Insfitution 3 



PAGE 



D. Appendices 201 



I. Dimensions and measurements of nets used in making our col- 

 lections 201 



II. Lengtli in meters of hauls made during July, 1912, with the 



Kofoid closing net 201 



III. List of hauls and water samples whose distances from the bot- 



tom are known to be within fifteen per cent of the depth 203 



IV. Abbreviations for character of the bottom adopted by the United 



States Coast and Geodetic Survey .' 204 



V. Tables for converting meters into fathoms and fathoms into 



meters 204 



VI. Table giving the length in meters of one minute of longitude for 



each degree of latitude from the equator to sixty degrees 205 



INTRODUCTION 



During- the past few years the data relative to the oceanic explora- 

 tions of the Scripps Institution have been in almost continuous 

 demand. Hydrographers have desired our temperature and salinity 

 records in order to complete their researches. Investigators publishing 

 fannistic papers based on material dredged by this institution have 

 repeatedly requested information concerning the season, locality, 

 depth, nature of the bottom, and other conditions under which the 

 specimens were obtained. Finally, the plankton records have been 

 urgently called for, particularly by those who. desiring to make 

 quantitative ecological investigations, could not proceed at all without 

 them. It soon became evident, therefore, that all our hydrographic, 

 plankton, and dredging records would have to tie published if we were 

 adequately to meet these demands. 



Accordingly, early in January, 1913, was beg-un tlie laborious task 

 of compiling and arranging the data which had accumulated during 

 the past twelve years. All the records of temperature, depth, position, 

 date, and so on, were carefully checked, whenever possible, against 

 the original field-notes and all the salinity determinations were twice 

 independently computed from the original measurements. It is thus 

 hoped that the numlier of occasional blunders consequent upon such 

 a vast amount of tabulation and computation has been reduced to a 

 minimum. 



In order to make the records available from as many points of 

 view as possilile, a description of the apparatus and methods of work 



