272 
PHYSIOLOGY: A. a MAYER 
being so, and if nerve conduction be a chemical phenomenon, we should 
expect according to Wilhelmy's law that its rate would be proportional to 
the concentration of these three cations which take part in the reaction. 
Thus if the particles of the colloidal nerve substance carry a negative 
charge they would attract these positive cations to their surfaces, in 
accordance with the well known formula Cs = /SCj^^ where Cs is the con- 
centration of the sodium, calcium, and potassium cations in the colloidal 
nerve substance; Ci is the concentration of these cations in the sur- 
rounding sea water; and jS and p are constants. 
TABLE II 
COMPOSITION 
OF THE SOLUTION 
RELATIVE CON- 
CENTRATION or 
THE CATIONS 
Na, Ca, AND K 
IN THE DILUTED 
SEA WATER 
OBSERVED 
RATE OF 
NERVE CON- 
DUCTION 
^0.866 
Natural sea water 
100.0 
100.00 
95 . 0 volumes of sea 
water + 5 .0 of distilled water. . . . 
95.2 
100.50 
0.51 
90.0 
« 
+ 10.0 
« 
it 
90.5 
95.89 
0.51 
85.0 
u 
+ 15.0 
it 
it 
85.5 
92.30 
0.51 
80.0 
« 
u 
+ 20.0 
it 
it 
80.8 
88.30 
0.50 
72.0 
ct 
« 
-f- 28.0 
it 
it 
73.3 
81.94 
0.50 
70.0 
<c 
it 
+ 30.0 
it 
it 
71.4 
81.40 
0.49 
64.0 
« 
(t 
+ 36.0 
it 
it 
66.0 
73.91 
0.52 
60.0 
(( 
il 
-t- 40.0 
it 
it 
62.2 
71.10 
0.50 
56.0 
(( 
u 
+ 44.0 
it 
it 
58.4 
64.55 
0.52 
50.0 
(( 
n 
-1- 50.0 
it 
it 
52.8 
56.31 
0.55 
33.3 
(t 
it 
H- 66.7 
it 
it 
37.5 
29.00 
0.79* 
* Injurious osmotic effects are produced by this extreme dilution. 
As appears in table II the conditions of this hypothesis are fulfilled 
down to concentrations of sea water diluted with an equal volume of 
distilled water, the exact formula being 
1 ^0.866 
C,= 2.QC\ ''\ Hence ^=0.5. 
As the rate of nerve conduction must according to Wilhelmy's law be 
proportional to Cs, we may substitute it for Cs. 
Thus apparently the velocity of nerve conduction is proportional to 
the degree of concentration of the cations sodium, calcium and potas- 
sium which are drawn from the surrounding sea water and concentrated 
by adsorption upon the surface of some undetermined negatively charged 
colloidal particles of the nerve. In fact the nerve stimulus which pro- 
duces pulsation appears to be conducted by these cations themselves, tak- 
ing part in some reversible chemical reaction accelerated by an enzyme. 
