74 Dr. Philip’s experiments to ascertain the principle 
the effect on the heart of stimuli so applied to the brain and 
spinal marrow, as not to excite any of the muscles of volun- 
tary motion, whose action, either by throwing more blood 
towards the heart, or in some other way influencing its action, 
prevents our judging of the effect of the stimulus. 
Exp. 12. A rabbit was deprived of sensation and voluntary 
motion by a blow on the occiput, the action of the heart sup- 
ported by artificial respiration, and the brain and cervical part 
of the spinal marrow laid bare. The thorax was now opened, 
and the action of the heart, which beat with strength and re- 
gularity, observed. Spirit of wine was then applied to the 
spinal marrow, and a greatly increased action of the heart 
was the consequence, It was afterwards applied to the brain 
with the same effect. The increase of motion was immediate 
and decided in both cases. We could not perceive that it was 
more in the one case than the other. 
Exp. 13. The foregoing experiment was repeated, with the 
difference, that the whole of the spinal marrow was laid bare. 
The motion of the heart was nearly, if not quite, as much in- 
fluenced by the application of the stimulus to the dorsal, as 
to the cervical portion of the spinal marrow ; but it was very 
little influenced by its application to the lumbar portion. 
Exp. 14. In this experiment, only that part of the brain 
which occupies the anterior part of the head was laid bare. 
The rabbit in other respects was prepared in the same way as 
in the preceding experiments. The spirit of wine applied to 
this part of the brain, produced as decided an effect on the 
motion of the heart as in those experiments. The spirit of 
wine was washed off, and a watery solution, first of opium, 
then of tobacco, applied, with the effect of an increase, but a 
