CASES OE IRREGULAR STRANGLES. 
491 
The heart would beat for five or six times successively ; 
then followed an interval of two, three, and sometimes even 
four seconds without any cardiac or arterial pulse being felt. 
The first pulsations succeeding this pause were always the 
strongest and nearest together, the next three or four beats 
became gradually weaker and slower, until succeeded by the 
period of pause or repose. On carefully examining the heart 
by means of the stethoscope, I could not detect an abnormal 
murmur accompanying either of the two cardiac sounds, nor 
could I feel satisfied that any structural disease existed in the 
walls of the heart itself. When the mare was taken out and 
exercised sharply, the second sound became inaudible until 
respiration fell to near its usual standard. This peculiarity, 
however, I have before noticed in cases where the lungs were 
congested in consequence of active exercise, or during the 
earlier stages of actual pulmonary disease. Repeated examin- 
ation of this case led me to conclude, that these peculiarities 
of cardiac action were due to functional and not organic 
derangement. 
The above symptoms continued, with little change, during 
the whole of June, except that towards the end of the month, 
a deep hoarse cough came on and rapidly increased in 
severity. The mare was tempted w ith various kinds of good 
food, but she took little. Mineral and vegetable tonics com- 
bined, were the only drugs administered. On July 2d, she 
became choked w 7 hile sw allowing some green food. A severe 
paroxysm of coughing came on at the same time ; at last 
she ejected great quantities of chewed clover and mucus from 
the nose. Gradual relief followed. I saw 7 her two hours 
after she had become quiet. She durst not eat again, and a 
small quantity of water was poured down the throat ; it could 
be felt passing in “ gulps,” down the cervical part of the 
oesophagus. On lowering her head, however, the fluid 
returned, and w as felt to come from within the chest. This 
denoted obstruction in the thoracic cavity. There w 7 as very 
great jugular venous regurgitation, the second cardiac sound 
w as very imperfect, but neither replaced nor accompanied by 
any murmur. Believing that the choking depended on some 
tumour or abscess in the antero-superior mediastinum, no 
probang was used. On relating this case to Professor Dick, 
he at once called to recollection other cases presenting these 
symptoms, where secondary abscesses, attendant on irregular 
strangles, w r ere found in the chest after death. It w 7 as there- 
fore decided merely to give the mare gruel and bran water. 
All food was withheld. 
During the succeeding week, the cough became of an in- 
