86 Dr. Philip’s experiments to ascertain the principle 
was passed round the neck of another rabbit of the same age. 
It was suddenly tightened, and the head cut off. In this in- 
stance little spasm took place, and the heart was found beat- 
ing regularly under the finger for about three quarters of a 
minute. At the end of this time, the ligature was slackened, 
and the blood spouted out to the distance of three feet, and 
continued to spout out with great force, till nearly the whole 
blood was evacuated. 
Exp. 23. From the strength of the spine of a rabbit, and 
the situation of the neighbouring parts, it is impossible to 
crush it, without directly influencing the state of the heart by 
the blow. We opened it between the cervical and dorsal 
vertebrae, and suddenly forced a steel rod through the cer- 
vical part. As in the experiments of M. le Gallois, the action 
of the heart was immediately debilitated. In the preceding 
experiments, the reader has seen, we repeatedly, slowly 
destroyed, or removed entirely, both the cervical and other 
portions of the spinal marrow, without at all influencing 
the action of the heart. 
These experiments point out an easy solution of the difficul- 
ties mentioned by M. le Gallois in the 119th and following 
pages of his Treatise. When the whole spinal marrow was 
destroyed by small portions at a time, comparatively little 
effect was produced on the heart ; but when a considerable 
part of it was crushed at once, the power of the heart was so 
impaired, that circulation ceased. So in other cases, where 
the injury was inflicted slowly, and where it was inflicted 
suddenly, the result was found to be different. 
Thus he observes, that if the spinal marrow be divided 
near the occiput, and a certain part of it immediately destroyed, 
I 
