THE INJURY CURRENT OF NERVE 
251 
EXPERIMENT A 
Vagus Nerve of Cat 
Nerve laid upon tour electrodes — A, B, C, D 
Length of AD (piece of nerve between electrodes A and D) ... 4-3 cms. 
BC ... ... ... ... ... r8 „ 
,, AB (distance of B from the cross- section) ... 1*3 ,, 
Resistance of AD directly determined ... 128,000 ohms 
„ BC ... ... ... ... 63,000 
,, a pair of electrodes ... ... 7,000 
„ circuit AD, including electrodes ... 135,000 
Calculated resistance of BC from the resistance per ) 
cm. obtained from (1) and from the length BC j 
Potential difference between A and D... ... -00712 Daniell 
1* 
B and C... ... o 
54,000 
(') 
(2) 
(5) 
These data having been collected, the experiment was performed :— 
(1) Electrode A was permanently connected to electrode D. 
The potential difference between points B and C was re-examined — B, the point nearer to 
the cross section, was found positive to C, the more distant point, by -0028 Daniell. 
The experiment was repeated rapidly several times, in each case B and C were equipotential 
when A was not connected to D, when this connection was made, B was positive to 
C, as given. 
(2) Electrode A was connected to D through 100,000 ohms, resistance — B positive to C again, 
but by -00168 Daniell. 
(3) Electrode A was connected to D by 150,000 ohms resistance — B positive to C, -00128 
Daniell. 
(4) Electrode A connected to D through 200,000 ohms — B positive to C, -00108 Daniell. 
Finally, the connexion between A and D being broken, B was found as formerly equi- 
potential to C. 
The potential difference between A and D, examined at the end of this experiment — 
A was negative to D, '00648 volt. 
EXPERIMENT B 
Vagus Nerve of Cat 
Nerve laid upon four electrodes — A, B, C, D. Cross section at A. 
Length of AD ... ... ... 6 - 2 cms. 
BC ... ... ... 2-6 „ 
AB o-8 „ 
Resistance of AD ... ... ... 204,400 ohms ... (1) 
BC ... ... ... 104,200 „ 
Pair of electrodes ... 6,000 „ 
Total resistance in circuit AD (nerve and electrodes) ... 210,400 ohms. 
Calculated resistance of BC obtained from its length and the 
resistance per cm. from (1) ... ... ... 85,800 „ 
