ON THE MOTIONS AND SOUNDS OF THE HEART. 197 
OssERVATION XVIII. 
Phenomena: Tubes introduced into heart's cavities; results ; 
—confirmations of former observations asto rhythm, pericardial 
frictions, changes of shape in the heart, §c., §c.; compara- 
tive sizes of ventricles. 
July 50th.—Operated on a Dog between one and two years 
old by prussic acid. Heart acting feebly, with the normal 
rhythm however ; the cavities considerably dilated. 
S. 1. Glass tubes containing strong solution of carbonate 
of soda, secured during the introduction by corks temporarily 
fixed in the wide end, were introduced by arapid rotatory mo- 
tion into the right ventricle and auricle. Owing apparently to 
awkwardness in the manipulation, the result was not through- 
out uniform to the eye; but the general character of what was 
observed was this: Columns of blood rose into the tubes in 
every case, and were perceived to overflow in each case witha 
slight jet in the systole of the cavity penetrated, and a slight 
subsidence in the diastole. At one time, for a minute or two, 
without interruption, the tubes were observed to overflow 
steadily together, one being in left auricle and the other in right 
ventricle, each having a slight jet, or upward undulation, in the 
systole of the cavity containing it. This experiment was com- 
paratively very striking, owing to the great difference in colour 
of the two streams, viz. scarlet, and deep crimson or purple. 
During the whole observation nothing occurred suggestive of 
impulse, except of the impulse upwards of the systoles of cavi- 
ties, and the slight gravitation or subsidence in diastole ; and 
this latter, though often very distinct in each tube, was some- 
times quite imperceptible in either. No motion downwards in 
the tubes, such as suction would explain, was observed. 
8. 2. After the observation the heart was cut out, and the 
_ left ventricle appeared rather larger than the right. 
_ 8. 3. The rhythm of the motions of the cavities; the auri- 
cular and ventricular double frictions of the pericardium ; the 
jerking upwards of the fundus and central parts of the ventricles 
in systole ; the shortening in systole; the stationary state of the 
heart amid all its changes of size and shape; the subsidence of 
the central parts and fundus in diastole, &c., &c., were noted 
to agree with former observations. 
OxsservaTions XIX. and XX. 
Aug. 5.—Operated by woorara on a Donkey two or three 
years old. Operation tedious, owing to strength and resist- 
ance of the animal. Also on a Dog. 
