336 PROFESSOR E. A. SCHAFER AND DR H. J. SCHARLIEB ON THE 
been arrested by chloroform ; and since it also has a stimulating action on the heart and 
respiratory centre, it is likely that it may prove useful as a restorative in cases in which 
the pulse and breathing have not altogether ceased. We have investigated the effect 
in dogs of causing them to inhale a mixture of chloroform vapour and ammonia, made 
either by dropping chloroform and ammonia upon the cotton-wool of the inhaling 
bottle, or by mixing chloroform in definite proportions with alcoholic ammonia, using 
for this purpose a solution of ammonia in absolute alcohol containing 6°8 per cent. of 
Fic. 21.— Instantaneous heart failure caused by inhalation, at the moment marked by the signal, of air charged with vapour 
from a mixture of 20 c.c. chloroform and 5 c.c. ammoniated alcohol. 
A, blood pressure ; B, respirations. The latter continued to show themselves at a slow rate for 3 minutes after the 
heart had stopped. 
ammonia, prepared for us by Messrs Duncan & Flockhart. A mixture of chloroform 
and ammonia vapours, even if it contain a comparatively small proportion of ammonia, 
is too pungent to be administered in the first instance, the irritation it causes to the 
sensory nerves of the mucous surfaces rendering it practically irrespirable. And if the 
proportion of ammonia be considerable, this excitation may result in powerful cardiac 
inhibition, and the heart may instantly and permanently stop (fig. 21). If, however, 
