19 
ably. At least two samples, a and h, made by the same firm, were 
bought on the open market and tested. In order to eliminate all 
bias the solutions to be tested were made by a second person. The 
relative efficiency of the original solutions was thus estimated and 
found to be as follows: la=70, lb=70; 2a=100, 2b = 86; 3a = 86, 
.3b=63; 4a=95, and 4b = 0. 
As already pointed out, Dakin and Stolz had synthesized com- 
pounds thought to be allied to adrenalin. Biberfeld (11) (1906) 
compared methylamino alcohol (synthetic dl-adrenalin) with natural 
adrenalin and found them physiologically identical. A 1:500,000 
solution causes dilation of the frog’s pupil; 2 mg. injected subcutane- 
ously into a rabbit causes diuresis and glycosuria; 0.001 of a milli- 
gram injected intravenously causes a rise of blood pressure. The 
lethal dose for rabbits is given as 0.1 to 0.2 mg. per kilo for intraven- 
ous injections and 4 mg. per kilo when injected subcutaneously. 
The reduction product of the aminoketone, ethylaminoalcohol 
represented by the formula 
OH 
NH(C,H3) 
is said to act more strongly upon the vagus, but to affect the blood 
pressure in a less degree than natural adrenalin. Diethylamino alco- 
hol was also found to be much less active. 
The amino alcohol represented by the formula 
OH 
/\ OH 
C^CH^NH, 
\OH 
produced a rise of blood pressure equal to that caused by natural 
adrenalin. In one case a rabbit withstood a dose of arterenol two 
to three times as great as the lethal dose of adrenalin without show- 
ing any very untoward symptoms of intoxication. 
Gunn and Harrison (36) (1908) dissolved samples of adrenalin in 
various kinds of media, preserving the 1:1,000 solutions in different 
kinds of containers and under various conditions, their object being 
