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Report on the Motions and Sounds of the Heart. By the 
Dublin Sub-committee of the Medical Section. 
The Committee having met together several times, and having 
considered different opinions hitherto advanced on the subject 
of the e Motions and Sounds of the Heart, 5 proceeded to insti¬ 
tute a series of experiments. The subjects chosen for experi¬ 
ment were calves, in which animals the heart is sufficiently large 
to admit of the motions and sounds being accurately observed; 
and their early age is favourable to a prolongation of the experi¬ 
ment, as it has been ascertained that the vitality of the different 
organs is more enduring, and less influenced by injuries to the 
individual, in animals at a very early age than in those of ma- 
turer growth. 
The animals were prepared for experiment in the following 
manner: a tube, connected with a pair of bellows, was intro¬ 
duced into the trachea, and secured there, and the sensibility of 
the creature having been destroyed by a blow on the head, arti¬ 
ficial respiration was established, by means of which the heart 
was enabled to continue its pulsations for a period varying in 
different subjects from one hour to two. The Committee had 
been unable to procure some of the Woorara poison, which has 
been used in similar experiments in London ; and they found 
that the employment of prussic acid, in a quantity sufficient to 
suspend the sensibility of the animal, destroyed, in a few mi¬ 
nutes, the power of motion in the heart. 
§ 1. j Experiments on the Motions of the Heart. 
Exp. 1 . A calf, two days old, having been secured on its back, 
and prepared as above described, the sternum, and a portion of 
the ribs on both sides were removed, when the heart was seen 
beating strongly, at the rate of 80 beats in the minute. While 
still inclosed in the pericardium, the heart was observed to have 
a slight libratory motion on its longitudinal axis, which motion, 
it may here be remarked, may assist in explaining the phseno- 
menon of c frottementf observed in disease. On cutting open 
the pericardium and turning it aside, both the auricular appen¬ 
dices were seen to project with a rapid motion upwards, oi to¬ 
wards the place of the sternum, and immediately afterwards to 
recede. When coming upwards, they were sw’ollen and soft to 
r 2 
