26 Transactions of the Boyal Society of South Africa. 
Fig. 2 gives an example of this obtained from a nerve sixteen hours 
after preparation. 
Garten" has shown that in experiments in which the leading-off elec- 
trodes are applied to two points on the uninjured longitudinal surface the 
action current may present itself, when the distal electrode is cooled, as a 
deflection of the galvanometer which would appear to indicate relative 
negativity of the cooled distal electrode. The explanation offered by 
Garten is that the action current at the distal electrode, although probably 
developed with less electromotive force than at the proximal electrode, yet 
persists considerably longer, and therefore exercises a predominant influence 
upon the galvanometer. 
Fig. 2. 
Kesponse from nerves after preservation for 16 hours in Kinger's fluid, without fresh 
section. The curve shows action current as downward or positive variation. 
Garten used the string galvanometer in his investigation, and the curve 
recorded under the conditions above-mentioned shows a deflection below 
the zero line during stimulation, caused by the predominant influence of 
the second phase of the action current, upon which the separate responses 
to the tetanising shocks are superposed. Garten assumes that if the two 
electrodes are at the same temperature the record will show merely rapid 
oscillations about the zero line corresponding to the diphasic action 
currents. 
I would put forward a similar explanation for the reversal of the 
variation accompanying activity obtained in my experiments. 
When the nerve is used immediately after removal from the body, the 
process of excitation is confined entirely, or almost entirely, to the uninjured 
* Pfliiger's Archiv. Bd. 136 S. 545, 1910. 
