The sun. [volume] (New York [N.Y.]) 1916-1920, 1919-09-28


area, these vessels reunite into large
vein which carries the blood back to
the heart at the opposite side.
The picture shows the heart as a
muscular organ which rtythmicaily
contracts, decreasing its volume and
thereby driving out the blood which
has flowed into II during the period OF
relaxation. In mammals and birds
there are two separate calculations.
The two pumps are combined side by
side; the right auricle and ventricle
form one pump. while the left auricler
and ventricle form the other.
The subject of the fourth scene Is
the heart of living embryo thirty
three hours old, showing its first
rhythmical activity and the course Of
the blood in the transparent heart,
cavity during contraction. /.
BIopd Pressure Develops. ?,
The next picture shows US a heart
of living embryo thirty-six hours old,
with body still transparent enough to
demonstrate the action of the arterial
heart valves. In the following picture
we see an embryo magnifled $50 times.
and we observe the circulation of the
blood In the right and left mesenteric
artery and the contraction Of its walls.
Next the vascular area is seen in detail
where the blood vessels, as they be-
come farther removed from the en-
| bryo, divide into smaller branches, and
there is evidence that an increased in
terpal friction results which causes
| considsfa BILE resistance in the flow of
blood. A high pressure is therefore re-
quired in the main arteries to drive
the blood through the small vessels.
Next we see the mesenteric artery
/ demonstrating the arterial flow OF
it divides into several branches, which
in turn are often connected by
anastomosis; then the arteriols in the
fore and mid-brain and the capillaries
in the hind-brain; then we see the
capillaries of the posterior vitelline
area, the posterior cardinal vein. the
capillaries of the anterior vitelline
vein, all leading back to the mesenteric
venous system and reaching the em-
bryo again at the right mesenteric
vein, where the even flow of blood is
nicely demonstrated
Many experiments have been made
in transplanting heart muscles into
a tissue culture to determine the con-
ditions which will prolong their life
| and function The heart OF a chicken
embryo will beat rhythnically from
six to ten days after having been re-
moved from the animal and trans
planted in blood plasna. But II
4 -
to time into fresh culture, II is
known that the muscles will live for
more than sixty days.
In order to obtain such cultures for
| he motion picture the heart of an
embryo is dissected into small pieces
about the size OF the head OF a pin,
and each piece transferred to a cover
glass and quickly imbedded in a drop
of blood pIasma. The cover glass is
then inverted over a hollow ground
slide and sealed with hot paraffln to
prevent drying; the prepared slide Is
then reincubated.
In the picture we see the trans
planted heart of an embryo eight days
old which is still beating rhythmically
after six days OF transplantation;
also a section of heart muscle fifty
times magnified showing It's rhythmi-
cal activity ten days after trans
plantation.
Scientific authorities agree that one
of the most valuable possibilities Of
such films lies in The fact that they
bring within the comprehension Of the
students mind a wide range OF in'
formation. thereby encouraging refieo'
lion, original thought and research.