qui prouvent le mieux, contre l’opinion de quelques
physiologistes, que les artères ont une action in-
dépendente de celle du coeur,” &c.1
Lastly, an argument for the muscularity of the
arteries, flows from observing the effect of elevated
temperatures upon these organic tubes. I had
observed that the batrachia, on being exposed to
water of 120°. of Fahrenheit, not only died almost
instantly, but that the superficial muscles became
rigidly contracted. I exposed the heart to the influence
of water raised to this temperature. It immediately
became small, pale, and rigid. It then
occurred to me that this experiment might confirm
or correct our views respecting the muscularity
of the arteries, and of other textures of the body.
A mere fibre of a longitudinal muscle was shortened
and made rigid ; a portion of membrane
or nerve underwent no change. An artery and
vein were now placed in the warm water: they
lay previously nearly equally flaccid upon a portion
of glass: the influence of the elevated temperature
was immediately seen in the artery, which became
rigid and cylindrical ; the vein suffered no apparent
1 De l’Auscultation Médiate. Ed. 3. Tome III. p. 359.
change. We have thus an important confirmation
of the opinion, that the arteries are possessed of a
muscular and consequently of a contractile tissue.
These experiments were made upon the different
textures of batrachian reptiles. In them a
temperature of 95°. of Fahrenheit, will induce
permanent contraction of the muscular fibres, A
higher temperature has, however, a similar effect
upon the muscular textures of the mammalia. This
subject will be treated more at length in a subsequent
part of this little volume.
Still it must be confessed that none of these
arguments are absolutely decisive. The facts afford
no distinct proof of the muscular action of
the arteries. The functions of these vessels are
mingled in the cases of the acardiac foetus and the
acardiac animal, in the fish tribe and in the Crustacea,
with that of the capillaries ; and, as we
shall have occasion to repeat hereafter, unless we
are enabled to separate these two orders of vessels,
it is impossible that we should ascertain the function
appropriate to each. The argument derived
from the structure and the augmented action of the
arteries, and the influence of an elevated temperature,
is more distinct. The apparent effect of
G