58 
other methods caused death in doses from one-quarter to one-half as 
large. In the one-hour method Digit alone No. 2, in doses four times 
as large as were given of the weakest and ten times as large as the 
strongest of the other (excepting Digitalone) preparations, failed to 
call forth systolic standstill of the heart. Digitalone No. 3 seemed to 
be fairly active. By the one-hour method on frogs it was from one- 
third to two-thirds as strong as the other preparations. Focke’s 
method was' not very successful on account of the extremely large 
dose which would have required so much concentration on the water 
bath to bring it to a volume small enough to inject into the lymph 
sacs. This specimen failed to kill guinea pigs when used in doses 
twice as large as the average preparation required. Injected into 
rabbits Digitalone No. 1 , instead of raising the blood pressure, dowered 
it 23 per cent, the curve resembling that given by the nitrite series. 
Digitalone No. 3 raised the blood pressure 26 per cent. 
An interesting fact in connection with the value of the blood-pres- 
sure methods of assay is that Digitalone No. 2, which was shown by 
the exposed frog’s heart to be almost devoid of digitalis action, caused 
a rise of 55 per cent in the blood pressure of two cats. It might be 
that some other substances are present (perhaps decomposition 
products) which, possessing no cardiac effect, yet act on the vaso- 
motor system, probably upon the center. In specimen No. 1 other 
changes in the solution must have occurred, as at each injection a fall 
in blood pressure followed. The important conclusion to be drawn 
from these experiments is that Digitalone is not invariably a perma- 
nent solution. Those preparations which have decomposed . are not 
only devoid of any digitalis action, but are distinctly harmful. A 
preparation which evidently had not deteriorated completely seemed 
to be about half the strength of an official tincture. 
