Of special interest is the technique developed to analyze for oxygen. 

 Four samples of sea water were taken at each station: (1) The first was 

 fixed in the water and taken to the habitat for analysis: (2) The 

 second was fixed in the habitat and analyzed therein: (3) The third was 

 fixed in the habitat and sent to the surface for analysis: (4) And the 

 fourth was sent to the surface for fixing and analysis. The procedure was 

 carried out in this manner so that the following information could be 

 obtained: By comparing the results of (1) and (2), one could determine the 

 effects of time, i.e., biological activity on the sample. (This would be 

 true because the sample would have seen only ambient pressure, about 2.5 

 atmospheres,) A comparison of (3) and (4) would tell quantitatively the 

 effects of a pressure change and the biological activity on the samples. 

 A comparison of (2) and (3) would give information about the dependence of 

 the analysis on pressure (which would probably be negligible) and would 

 serve as a check on the relative precision on the analyst below and topside. 



RESULTS 



The data given in Table 1 below are average values based on 24 runs. 



TABLE 1. 



Group ml O 2 /I seawater 



(1) 5.26 



(2) 5.26 



(3) 5.32 



(4) 4.22 



There is no doubt that the greatest change occurs when a sample of sea 

 water is taken from native environment and brought to the surface for fix- 

 ing and analysis --an average decrease of 207o in the oxygen content was 

 noted: These data strongly suggest that the hypothesis made in the intro- 

 duction of the paper has real merit: indeed, the changes in pressure as a 

 sample of sea water is brought from its environment to the surface are 

 large enough to effect degassing of the sample provided that the concentra - 

 tion of oxygen at depth exceeds the surface saturation values . (The 

 saturation values for oxygen-saturated sea water is about 4.3 milliliters 

 per liter. This value is indeed the limit to which most of the samples 

 tend . ) 



It should be pointed out that on our return trip to TEKTITE II in October 

 the concentration of oxygen at depth was considerably less than the surface 

 saturated value, and because of this no degassing of oxygen occurred aas 

 the sample was brought from the bottom to the surface. On the basis of 

 elementary thermodynamic reasoning, it is eminently reasonable to assume 

 that samples of sea water would degas as they undergo decreases in pressure; 

 the rates at which this degassing effect occurs is still unknown but it 

 appears to be approximately 2-6% per hour. If this is true, then certainly 

 much of the data accumulated on the oxygen concentration as functions of 

 depth should be reconsidered in the light of these new findings. 



VI-18 



