394 Prof. Curistison on the Poisonous Properties of Hemlock, 
length of time. I have seen spontaneous contraction of the ven- 
tricles of the heart go on ten minutes, twenty minutes, nay, even 
thirty minutes, after death in the rabbit; and have witness- 
ed unequivocal contraction of the auricles when scratched even 
so late as after an interval of sixty minutes. The most striking 
illustration, however, of the integrity of the function of the heart 
is obtained by keeping up respiration artificially when it has 
ceased : After the breathing had almost ceased in seventeen mi- 
nutes in a dog poisoned with six drops through a wound, and 
when two minutes more would undoubtedly have put an end to 
life, artificial inflation of the lungs was commenced, and conti- 
nued with occasional intervals for thirty-five minutes. During 
all that time the heart beat with its natural force, except when 
the inflation of the lungs was suspended ;—the animal remaining 
all the while in a state of paralytic flaccidity, interrupted only by 
slight muscular twitches. It appears probable that there is 
scarcely any limit to the maintenance of the circulation under 
artificial breathing, except what may arise from the difficulty of 
imitating exactly the natural respiration, as well as from the se- 
veral causes which occasion cooling of the body. ‘There is little 
doubt, therefore, that where the dose of the poison is not very 
great, animation may be restored by maintaining the function of 
respiration artificially till the deleterious agent or its effects be 
thrown off,—just as in some other forms of narcotic poisoning. 
And when we consider the whole physiological phenomena, it 
will appear that this is the only treatment which promises mate- 
rial success. 
There are several other physiological facts relative to the 
action of this poison, which are not devoid of interest, but which 
it would be tedious to dwell on here. They will be best exa- 
mined by consulting the Appendix of experiments. This de- 
partment of my subject, therefore, may now be concluded with a 
few remarks on the question, through what channel the action of 
conia on the spinal chord is accomplished : Does it act by being 
