CRYOSCOPIC AND OSMOTIC DATA. 



79 



minations of the Pacific Grove sea water and found that A = 

 — 1.924° C, Garrey in 1905 made determinations, obtaining a 

 slightly lower value for A viz., — 1.905° C. On the basis of either 

 of these figures, it is seen that the sea water in this locality is 

 about 5 per cent, more concentrated than at Woods Hole and 

 that a correction for this amount must be made if the osmotically 

 equivalent solutions are to be calculated from the figures given in 

 the previous section {a). 



(c) Beaufort, N. C. — ^Working in the laboratories of the U. S. 

 Bureau of Fisheries during the summer of 191 1, the author made 

 the following observations of the freezing point of sea water 

 obtained at different localities in that vicinity and under different 

 conditions as described in Table II. 



Table II. 



Beaufort, N. C. 



Open sea, outside "Sea Buoy" 

 Wharf of U.S.F.C 



Wharf of U.S.F.C 



Wharf of U.S.F.C 



Open sea, at ".Sea Buoy" 



Wharf, U.S.F.C 



Wharf, U.S.F.C 



Bogue Sound 



Wharf U.S.F.C 



Sea Buoy 



Wharf, U.S.F.C 



Newport River, at "Cross 

 Rocks" 



:°C. 



June 8 



July 19 



" 20 

 " 25 



Sept. 6 



-2.043 

 -1.987 



-2.015 



-2.038 



-2.03 



-2.07 



-2.06 



-2.073 



-2.079 



-2.05 



-2.052 



-1.707 



11:40 a.m. — tide low, N.E 

 wind, previous showers. 

 4:00 p.m. tide high 



9:15 a.m., tide low 

 3:00 p.m., tide high 



Tide low, strong south wind 



Tide low 



From these figures it is seen that the open sea water off Beau- 

 fort has a A = — 2.04° C,, and is 12 per cent, more concentrated 

 than at Woods Hole. 



(d) Diluted Sea Water. — The constant necessity for the use, in 

 biological investigations on marine forms, of diluted sea water 

 and corresponding concentrations of pure salts, has led the 

 author to make the determinations found in Table III. Various 

 dilutions of Woods Hole sea water were made and the freezing 

 points determined. In most cases the densities at these dilutions 

 have also been determined by the pycnometer method. The 

 figures given in the table are all from actual determinations made 



