OCEANOGRAPHY: A. G. MAYER 
549 
equilibrium with the carbon dioxide of the atmosphere, and thus still 
retains some of the relative acidity associated with its former low 
temperature. 
Similarly, we would expect cold currents drifting into warmer regions 
to retain their relative acidity to a greater degree than is warranted by 
their augmenting temperature; and this expectation appeared to be 
justified by the very low alkalinity of 0.141 X 10~^ shown by the water 
at 10?5 C, 54 miles W.S.W. of Golden Gate, San Francisco, on May 1, 
1917. 
No conclusions should be drawn from such meagre observations, but 
if future studies should demonstrate that low alkahnity is usually asso- 
ciated with easterly set of surface currents over the tropical oceans, 
the fact may become of importance to navigation owing to the ease and 
rapidity with which colorimetric tests of the alkalinity of sea water 
may be made by using a graded series of thymolsulphonephthalein tubes 
in the manner suggested by McClendon. In response to a request from 
Professor McClendon, tests were made of the carbon dioxide of the atmos- 
phere at noon each day, but these showed that there is apparently no 
definite relation between the CO2 tension of the air and the local alkalin- 
ity of the surface water. 
The CO2 tension was very variable and ranged from about 0.00045 to 
0.00025 of an atmosphere, the average of 22 determinations being about 
0.00035. There is also no definite relation between the salinity and the 
hydrogen-ion concentration of the ocean water, as will appear from the 
following tables. 
The cold current which moves southward along the coast of CaHfornia, 
is of low saHnity being about 33.6 or 33.7 on an average whereas the sa- 
linity of the water between 1000 miles off the CaHfornian coast and the 
Hawaiian Islands is about 35. 
An elaborate study of the salinity and temperature of the water off 
the California coast has been made by George F. McEwen, University 
of California Publications, Zoology, 15, 1916, (255-356, Plates 1-38), and 
the presence of an upwelling of cold water from the depths is clearly 
indicated along the CaHfornia Coast as a result of studies by Michael 
and McEwen. 
