618 
OCEANOGRAPHY: J. F. McCLENDON 
These experiments cleariy show that the surface water of the sea is a 
supersaturated solution of CaCOs and it is only necessary to introduce 
calcite crystals in order to cause considerable precipitation of this sub- 
stance. Precipitation goes on in the bodies of organisms in the surface 
waters of all seas. The precipitation observed by Vaughan at Tortugas 
is very finely divided, but whether it was formed in the bodies of minute 
organisms, which subsequently died, has not been determined. Such 
particles might slowly grow, since the agitation of them with sea water 
was found to take a trace of CaCOs out of the water. Small crystals 
have been seen in the bodies of Protista, and whether they are CaCOs 
or not, they might form nuclei for the precipitation of CaCOs if released 
into the sea water. 
In some experiments in liter flasks of resistance glass, filled into the 
neck (and hence admitting of but slight loss of CO2) the pH and alka- 
line reserve was determined immediately before and after agitation 
with calcite, and the loss of CO2 from the sea water calculated from the 
pH and from the loss of CaCOs (alkahne reserve). 
CALCULATED LOSS OF CO2 
SEA WATER 
pH 
TOTAL CO2 
ALKALINE 
RESERVE 
From pH 
From alk. res. 
Before agitation with calcite 
8.2 
44.5 
0.0025 
6 
6.72 
After agitation with calcite 
7.67 
38.5 
0.0019 
Before agitation with calcite 
8.25 
43.8 
0.00250 
6.8 
7.27 
After agitation with calcite 
7.72 
37.0 
0.00185 
In the above table, the agreement is very striking in view of the 
probable error in determination of pH and the liability to loss of CO2 
from the water surface in the neck of the flask, agitated by the rotary 
stirrer. 
If the pH of sea water should be maintained (by the action of plants) 
at 8.2 while it was agitated with calcite crystals, the loss of CaCOs 
would be about 0.001 N, or 0.0005 M, or 0.1 gram per hter. This 
would cause a deposit of 10 kgm. per square meter of bottom in water 
100 meters deep. This would cause a lowering of the calcium content 
of Tortugas sea water by about 4.5%. 
1 The Depths of the Ocean, London, 1912, p. 178. 
2 These Proceedings, 2, 1916, (28). 
2 Washington, Carnegie Inst., Pub. No. 182, 1914, (Tortugas Lab., vol. 5). 
^ Depths of the Ocean, p. 368. 
^ Voyage of H. M. S. Challenger, Physics and Chemistry, vol. 1. 
6 McClendon, /. Biol. Chem., Aug., 1917. 
