265 
ANEURISM OF THE AORTA, &C. 
account for : it was, however, obvious that it could only proceed 
from a vessel of the largest caliber, and that it must be in the 
posterior aorta, not in the vertebral artery. On a more careful 
examination of the parts, no traces of inflammation could be per- 
ceived, nor any thing abnormal ; and as the animal did not flinch 
on pressure, Herr Rohling concluded that there must be some ob- 
struction in the aorta; though of what nature the obstruction was, 
whether contraction of the vessel or otherwise, it was impossible 
to determine. 
The same treatment was continued. On the 18th the patient 
laid down more frequently in the aforementioned position, looked 
often and anxiously at his back, and grunted often and pain- 
fully. Pulse 18 per minute: 18 pulsations were also felt on the 
side of the spine, whose oscillations were, as before, towards the 
chest. The respiration was 18 per minute, but without being 
laborious. The respiration and the pulse at the brachial artery 
and the back were synchronic. The contractions of the heart were 
bounding. Appetite none. A few swallows of cold water were all 
that was taken. On the 19th, at six in the morning, the mare 
died. At twelve the same day Herr Rohling made a post-mortem 
examination. 
On opening the abdominal cavity, the large intestines, colon 
and caecum, presented no abnormal aspects. On removing them, 
the small intestines, posterior part of the pancreas, and the cel- 
lular tissue surrounding the kidneys, shewed traces of inflamma- 
tion. The anterior mesenteric artery was enlarged to the size of 
a man’s fist., of a very dark colour, very hard; and at the junc- 
tion with the aorta both vessels were filled with a hard substance 
formed by the crassamentum of the blood, so that it was next to 
impossible for the blood to circulate through this mass to reach the 
posterior part of the vessels. The part of the aorta anterior to this 
tumour, up to the heart, was filled with thin dark-coloured blood. 
The remainder of the abdominal organs were healthy, and like- 
wise those of the chest. Only the heart and lungs with the ante- 
rior aorta were filled with a quantity of thin extravasated blood. 
It was at the autopsy alone that the disease (aneurism) of the an- 
terior mesenteric artery became apparent. The inflammatory pro- 
cess, which had terminated in gangrene, had involved the sur- 
rounding parts, particularly the aorta at the part where the mesen- 
tery is given off. By the exudation of the serum of the blood the 
solid part had obstructed both vessels, whereby the circulation had 
become so much impeded that it had almost entirely ceased. This 
discovery led to the following reflections : — 
The rare pulsation of thp aorta felt at the side of the spine, the 
vibration of the vessel towards the heart, was the effect of the con- 
VOL. XXIII. N n 
