426 _ Mr. W. L. Symes and Dr. V. H. Veley. [ Dec. 10, 
Table III.—Stovaine. 
Time required | Duratj f 
Concentration. Temperature. to block maximal | Bl As : 
stimulus. ; ped 
| °C. mins. mins 
IN/100 (0:27 pericent.)--..... 18 1 4, 
BORE | 10 2 4 
IN SOON ieee ce nanset emer oeee ii | <lk 7 
bpd Oe eee | 17 4, 3 
IN GOOG 0is.2 + ostaete oes Ral 19 ‘3 9 <1 
IN/LOOO ©. 25%. eeeomtn ce eel 19 °3 17 <1 
be io tache eee eh ee 28 3 <1 
18 4 <1 
Methyl Stovaine. 
Methyl stovaine closely resembles stovaine in rate of action,* but its 
effect subsides more rapidly when the nerve is replaced in saline. Its affinity 
value has been found by one of ust to be somewhat greater than that of 
stovaine. It may therefore offer some advantage over the latter, since its 
base is less readily precipitated by faintly alkaline solutions such as cerebro- 
spinal fluid or lymph. 
Table IV.—Methy] Stovaine. 
Time required Duration BE 
Concentration. Temperature. to block maximal “bl OES 
| : ock. 
| stimulus. 
| : ee = 
°C. mins. mins. 
N/100 (0 ‘26 per cent.)......... 17 ‘8 1 >20 
IN/300) “2 snserseserent esses 20 11 8 
sj sep bis dns Sac a otis Seer eenet V7 92 3°5 1 
IN/ BOO? se cleecoe ae natn 20 153 <1 
itm boseahe. diate ee ene peoere 17 ‘2 6 <l 
Amyl Stovaine. 
Close comparison between this and the preceding drugs is difficult owing to 
gradual precipitation of its base by tap water. Solutions in tap-water saline 
act more slowly than equimolecular solutions of stovaine, or of methyl 
stovaine, but the resulting block is of greater duration. In distilled water 
saline, it both acts and is washed out rather more rapidly, though less so 
than the other drugs mentioned above. It, therefore, offers the advantage of 
* Of: Veley and Waller, loc. cit. 
+ Veley, ‘Trans. Chem. Soc.,’ 1909, vol. 95, p. 758. 
t Solutions of amyl stovaine are more readily decomposed by boiling in soft glass 
vessels than are those of stovaine. 
