8 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 60 



Comparing the known average density of the surface water of the 

 Philippine archipelago, about 1.02675, with the average of the ob- 

 servations taken by the " Albatross," 1.02453, we find the latter to be 

 0.00222 too low. Possibly part of the difference is due to the excess 

 of salinities taken near the shore in the " Albatross " records. 



Comparing the known average density of the deep water of the 

 Pacific, 1.02650, with the average of the eighty observations taken 

 by the "Albatross " below 100 fathoms, 1.025048, we find the latter 

 to be 0.00145 too low. A glance at the records suggests that the 

 difference really is somewhat greater, for the water bottles evidently 

 did not always contain water from the depth to which they were sub- 

 merged. 



A similar comparison of the densities as given by Makaroff, and 

 as determined by myself in the same localities at six well separated 

 places show my observations as calculated to be too low by 0.00136, 

 0.00184, 0.00215, 0.00210, 0.00115 and 0.00175. 



If we average these differences between the observations taken on 

 the " Albatross " and those taken by the British, German, Swedish 

 and Russian ships we will get a correction which, when applied to the 

 former, will make them comparable to the latter, or at any rate 

 nearly enough so for the purposes of the present study. The average 

 of these eight differences is 0.00175, which is the correction which 

 will be used throughout this paper. The average of my six obser- 

 vations which are comparable to those of Makaroff, all of which were 

 calculated by the same observer, is 0.00173. 



On plotting my observations, corrected by comparison with the 

 determinations of Makaroff on the western side of the Pacific upon 

 a chart, I found that one of my stations was almost on the exact 

 spot occupied by a station recorded by Lenz, in the Gulf of Alaska, 

 and I was gratified to find that the salinity given by Lenz, and my 

 own determination of the salinity with the empirical correction 

 added, were identical. 



It will be noticed that all of the salinity records published by 

 Mr. Alexander Agassiz for the mid-Pacific region which were taken 

 on board the " Albatross " are in need of about the same correction 

 to make them comparable with those of the ships of other nations. 



The necessity for this correction arises from the fact that the 

 instruments were not standardized before beiner used. 



