moving the whole nervous masses at once, or small
portions of them at distant intervals. And I
suppose that the medulla oblongata is removed
with the brain and spinal marrow.
It was after having watched the experiment given,
pp. 130, 131, and finished its details, that these
views occurred to me. It was nine o’clock, A. M.
Thirty-six hours had elapsed from the time at
which the medulla oblongata was destroyed. I
removed the entire brain and spinal marrow. At
one o’clock, four hours after the whole of the
brain and medulla was removed, the circulation
was still obvious enough in the arteries, capillaries,
and veins, and likely to continue, although paler
and more languid. At four o’clock, there was
still an obvious movement of globules along the
arteries and veins. And even at nine o’clock there
was still a very slight degree of circulation in the
minute arteries and veins.
To this experiment the following one may
be added:
Similar phenomena were observed in the subsequent
progress of the experiment detailed in
p. 135. At eight o’clock in the evening, rather
more than twenty-four hours after the destruction
of the spinal marrow, the respiration, and the
capillary circulation continued good ; the fine wire
was now passed upwards so as to destroy the
medulla oblongata and brain. Respiration ceased^
The circulation in the web was immediately
enfeebled ; an artery distinctly seen, became much
enlarged, but not distended. In ten minutes the
circulation was feebler still; the rapidity became
nearly the same in the arteries and veins. On the
succeeding morning and evening, the circulation
still continued. It was still obvious and indeed
apparently little altered on the third day, after
noon, forty hours after the entire destruction of
the brain and medulla. In the evening all circulation
had ceased ; and on exposing the heart
there was no pulsation.
The first part of these several experiments
reduced the animal many degrees in the scale.
In the first experiment it subsisted without medulla
oblongata or pulmonary respiration. Its nervous
system was reduced; its respiration was merely
cutaneous. In this state, it was enabled to endure
the further and entire privation of its brain and
spinal marrow without the immediate cessation of
the power of circulation. In the second experi