722 
PHYSIOLOGY: A. C. MAYER 
series being 7.93 PH. or 1.17 X 10~^ hydrogen ion concentration. Its 
alkalinity was probably due to soda derived from the glass carboy, 
the balance being maintained by a tendency of the water itself to be- 
come acid through leakage of CO2 from the air. Professor J. F. Mc- 
Clendon found the PH. of the Tortugas sea water to range from 8.1 
to 8.22, and dilution with alkaline distilled water of 7.93 PH. main- 
tained the normal hydrogen ion concentration of the sea water even 
when diluted with its own volume of such distilled water. 
TABLE I 
Illustrated by Figure 1 
COMPOSITION OF THE SOLUTION 
I 
RATE OF NERVE 
CONDUCTION 
WHEN THE SEA 
WATER IS DI- 
LUTED WITB ACID 
DISTILLED 
WATER OF 6.04 
PH. AT 30°C. 
PROBA- 
BLE 
ERROR 
II 
RATE OF NERVE 
CONDUCTION 
WHEN THE SEA 
WATER IS DI- 
LUTED WITH 
ALKALINE DIS- 
TILLED WATER 
OF 7.93 PH 
AT SOX. 
PROBA- 
BLE 
ERROR 
III 
RELATIVE ELEC- 
TRICAL CON- 
DUCTIVITY OF 
TORTUGAS SEA 
WATER DILUTED 
WITH DISTILLED 
WATER OF 
7.8PH.AT30X. 
Natural sea water of 8.1 to 8.22 
PH 
100.00 
100.00 
100.00 
95 cc. sea water + 5 cc. distilled 
water 
96.43 
0.74 
96.23 
0.67 
90 cc. sea water + 10 cc. distilled 
water 
94.38 
0.88 
91.44 
1.00 
92.16 
80 cc. sea water + 20 cc. distilled 
water 
82.68 
1.16 
79.51 
1.18 
81.38 
70 cc. sea water + 30 cc. distilled 
water 
71.95 
1.13 
73.91 
1.16 
71.53 
60 cc. sea water + 40 cc. distilled 
water 
60.41 
0.59 
65.72 
1.01 
64.26 
50 cc. sea water -\- 50 cc. distilled 
water 
50.83 
0.90 
54.16 
0.79 
54.08 
It will be seen by comparing columns II and III of the above table 
that when alkaline distilled water of about 8 PH. is used to dilute the 
sea water the decline in rate of nerve conduction is practically the same 
as the decline in the electrical conductivity of the sea water when simi- 
larly diluted. We should remember, however, that the concentra- 
tion of the sodium, calcium and potassium cations declines in prac- 
tically the same ratio and thus the rate of nerve conduction may be 
proportional to the concentration of these cations rather than to the 
electrical conductivity of the diluted sea water as a whole. 
However, Prof. Ralph S. LilUe is right in a recent paper (Amer. J. 
PhysioL, 41, 123) wherein he states his behef that the rate of nerve 
conduction in Cassiopea in diluted sea water does not decline in accord 
