The Pioche weekly record. [volume] (Pioche, Nev.) 1877-1900, 1891-05-14
VIvISECTION.
An Object Lesson on tho Movements OF
the Heart.

An Object Lesson on tho Movements OF
the Heart.
Vivi cotton is allowed under certain
restrictions in New York State, says the
New York Herald, and that paper gives
the following account of Dr. John Green
Curtis operation on calf to show his
class the physiology of the hearts ac-
ton:
DIR. Curtis was covered from neck to
knee by gown for protection from
blood stains, and as he waved his hand
to the ianitor and his young assistants
he looked not unlike some ancient high
priest awaiting the victim of a sacrifice.
The calf had already been strapped to
a frame that conformcd closely to the
shape of his body. This was mounted
on wheels to facilitate its easy move.
mont in various directions. The ether
was given while the doctor talked, and
he was frequently interrupted by a
plaintive ''bah!'' or deep sigh from his
victim. lie first performed tracheotomy
and then resorted to artificial respira-
ton, which was done by applying a
piece of rubber hose from a stationary
pair of bellows to the tracheotomy
tube inserted into the animals wind
pipe, and thus pumping in air, the
ether sponge being applied to the valve
| of the bellows, etherizing all the air
forced into the animals lungs.
A triangular section of the ribs and
carriages and breast-bone was cut
away and the parts directly beneath
dissected from it carefully. Beneath
was revealed the Serious sac containing
the heart and the roots of the great
arteries. This is known as the peri
cardium The professor deity slit
this open from bottom to top with
pair of scissors, and on open
ing it the heart, with its append
ages, came to view. The motion Of the
heart as it beat, sending the fluid of life
through the system, was thus shown, its
right side being rather darker than the
left from the venous character of the
blood passing within, while the brill
iantly colored arterial blood gave the
left side its higher color.
"Observe," said the professor, that
the same action is taking place in both
sides OF the heart at the same time; the
two ventrioles contract and expand at
the same moment and the long axis of
the organ shortens in systoles and
lengthens slightly in diastoles. In sys-
toles its circular fibers slightly twist it,
while in diastole it untwists again.
1.-THE circulation of the blood is best
shown by the puncture of Harvey. This
is to push trocar into the ventricles,
which, If blood is passing into it, will
squirt it out jet after jet in the air." Aft
or giving the class good chance to
study the hearts movement beat the
professor plunged hollow needle OF
trocar, about oneeighth Of an inch in
diameter, into the left ventricle, and jet
after jet came jumping out, driven by
the pump-like action of the organ, thus
showing that blood was being constant
ly forced onward or kept in circulation
by the contraction of the organ.
TO complete the vivisection and to be
sure that the animal should not suffer
any pain the professor and his assistants
now opened the back of the animal.
neck and severed the medulla oblongati
I as high as the base of the skull. The
heart ceased beating victim was
dead. The animal had lived over al
hour with its heart exposed, and so per
, feet was the vivisectors skill that thu
, hearts action did not even seem to weak
en- in all that time, nor was there thu
, slightest sign of pain.