1910.] Physiological Properties of Stovaine, ete. 417 
(COOC3H;) groupings produces a decrease of rate of action while that of 
methyl is less marked, the differences observed being within the limit of 
experimental error. As regards the amyl, phenyl, and benzyl derivatives, 
it is possible that the differences observed may be due to the precipitation 
of the bases as pointed out above. 
B. Lffect on Blood-presswre and on Respiration. 
Though it was not possible to carry out, 7m vivo,a complete investigation 
into ‘the physiological action of these bodies, it nevertheless seemed of 
interest to employ some of the material at our disposal for the purpose of 
comparing their respective effects, with those of cocaine, on the circulation 
and respiration of the mammal. 
The number of observations is not large enough to warrant close 
quantitative estimation of their individual toxicities, but suffices to enable 
comparison of the type and (to some extent) of the degree of their effects. 
In all cases the animals employed were cats, under complete anesthesia, 
and the drugs were administered by injection into the saphenous vein. 
Cocaine. 
As is well known, cocaine in sufficiently small doses is a cardiovascular 
and respiratory stimulant. On cats with intact central nervous system, 
blood-pressure was raised by doses of 0:°05—0°7 mgrm. per kilo. body weight, 
lowered by larger doses; whilst on a completely pithed cat. injections 
produced no fall in doses up to 19 mgrm. per kilo. On the respiratory 
movements, the depressant action of the drug has appeared with smaller 
- doses than on the blood-pressure. 
Stovaine and Methyl Stovaine. 
These drugs have not, with us, raised blood-pressure or stimulated respira- 
tion in any dose. Small doses, when effective, led to fall of blood-pressure . 
of varying amount and duration, together with a momentary pause in 
respiration, which was followed by a rhythm of greater frequency and 
smaller amplitude than that before injection. A single (first) dose of 
stovaine amounting to 5 mgrm. per kilo. has proved fatal, but provided that 
the initial doses were small, single injections amounting to three times as 
much did not cause death, and a total dose of 40 mgrm. per kilo. can be 
tolerated. With methyl stovaine an initial (single) dose of 8:4 mgrm. per 
kilo. did not produce any obviously dangerous effect. As on muscle* and on 
* Veley and Waller, loc. czt. 
