ROYAL IRISH ACADEMY. 
289 
sial union—does not exist. There is nothing to lead us to suspect that 
any malformation by defect exists in the heart. 
When the subject is in a state of quiescence, the following pheno¬ 
mena can be observed on inspection and examination of the sternal 
fissure:— 
1st. The existence of a pulsating tumour, of an elongated oval shape, 
of about two inches in length; it crosses the mesial line obliquely, so 
as to show about two-thirds of its volume to the left. 
2nd. The pulsation of this tumour, though plainly visible at a dis¬ 
tance, is by no means forcible. It has not the strength of the systole of 
a healthy heart, nor yet the force of the beat of an aneurism; and it 
does not convey the sensation of proceeding from a cavity with thick 
or solid walls. 
3rd. The collapse of this tumour is much more sudden than its pro¬ 
trusion. It appears to be second in point of time. 
4th. This collapse or disappearance of the tumour is, however, ef¬ 
fected with a progressive movement from above downwards. This is 
rendered obvious by the observer placing three fingers lightly on the 
pulsating mass. Their successive elevation shows the course of the 
movements as above stated. 
5th. This pulsation was ascertained to be not synchronous with the 
beat of the apex of the heart, but to precede it by a slight though appre¬ 
ciable interval of time. 
6th. The diastolic movement seems to take place in a direction from 
the left and behind, forwards and to the right. 
7th. On applying the finger lightly over this tumour, the pulsation 
is observed to be single. 
8 th. On more deep and forcible pressure backwards and slightly to 
the left side, a double stroke is felt. 
9th. On deep pressure backwards in the upper part of the fissure, a 
distinctly double pulsation can be perceived. 
10th. This second pulsation, we submit, is that of the arch of the 
aorta, of the innominata, or of both. 
11th. This pulsation (that of the arch of the aorta) follows, by the 
shortest appreciable interval, upon that of the heart’s apex. 
12th. It is also consecutive, but by a more prolonged and sensible 
interval, to the pulsation of the oval-shaped tumour. 
13th. The order of succession of the phenomena here described is 
well displayed and confirmed by the application of the sphygmoscope. 
14th. The heart was examined with the stethoscope in the usual 
situation, and presented the ordinary first and second sounds, quite de¬ 
void of any abnormal character in tone or rhythm. 
15th. Auscultation over the seat of the aorta gave the two sounds 
peculiarly well defined, the second in particular being remarkably clear 
in this situation. 
16th. In no part of the cardiac region, or in the line of the. great 
vessels, was any murmur or other abnormal sign discoverable. 
17th. Occasionally the second sound lost its usual definite and sin- 
