422 Mr. W. L. Symes and Dr. V. H. Veley. [ Dec. 10, 
The local anesthetics which we have compared in this way are cocaine, 
stovaine, the methyl-, amyl-, phenyl-, and benzyl-homologues of the latter, 
and anew salt prepared by Fourneau, viz., the propyl ester of a dimethyl- 
amino-oxybenzoyl-isobutyric acid, which as elsewhere* pointed out, is inter- 
mediate in chemical structure between cocaine hydrochloride on the one 
hand, and stovaine on the other. In addition to their bearing on the com- 
parative effects of individual drugs, our results throw light on the response 
of nerve to direct, and on that of muscle to indirect, electrical stimulation. 
II. METHOD oF EXPERIMENT. 
Most of our observations were made on the isolated nerve-sartorius, with 
a light myograph, in a moist chamber. The stimuli were maximal break 
induction shocks, applied to the nerve at intervals of 10 seconds, just below 
its divergence from the main sciatic trunk. 
La Lage gy ELLIE CEL e hada deen tise Vy yaseny py LQUV Pde bt eddie TOES SEPP COPEL POU Err pr pein y 
Fig. 1.—Blockage of Conductivity (local anesthesia) in nerve by Fourneau’s new salt 
N/100 = 0°29 per cent. solution. 
. . - | Nerve in normal saline—preliminary test of preparation. 
1... 2 Nerve in anesthetic solution—onset of blockage. 
2... . Nerve in normal saline—restoration of conductivity. 
The lower line signals minutes (down strokes) and stimuli (up strokes). 
Between the electrodes and the muscle, approximately 2 millimetres from 
the latter, about 1 centimetre of the nerve was immersed in a bath con- 
taining successively :— | a 
A. Normal saline solution (0°6 per cent. NaCl in tap water). 
B. A solution of one of the drugs in normal saline. 
C. Normal saline again. 
us Veley and Symes, supra, p. 414. 
