324 
Proceedings of the Royal Society 
the heart and lungs were cut out together. While this was being 
done, the heart was observed to give a few pulsations, which led 
the butcher to remark that the animal was not quite dead. A 
string was then firmly tied round the great vessels at the base of 
the heart, which was next separated from the lungs by cutting the 
vessels on the distal side of the ligature. The heart on being laid 
aside on a table began to pulsate slowly but rhythmically, the 
contractions taking place in both auricles and ventricles. After a 
few minutes spent in examining the remaining viscera of the 
animal, and of others killed at the same time, the heart and portions 
of other organs were wrapped up together, and carried to the 
University Uew Buildings, the Abattoir being left at 10*35. 
At 10.50, wdien the parcel was opened in the Pathological 
Laboratory, it was observed that spontaneous contractions were 
still occurring at intervals in the auricles of the heart. On 
stimulating the right auricle by slight scratching with a pin, a 
contraction of that cavity was easily obtained, and this was 
immediately followed by contraction of the left auricle. Stimula- 
tion of the left auricle produced a contraction of that cavity, but 
did not affect the right auricle. These experiments were repeated 
several times, and always with the same result. 
Both auricles continued to beat spontaneously till 11.12, the 
contraction occurring first in the right, and this being followed 
immediately by a contraction of the left. 
After 11.16 contractions of the left auricle were obtainable only 
by direct stimulation, the right auricle, however, continued to beat 
till 11.19. 
At 11.28 fibrillary twitchings were obtained on slightly stimu- 
lating the posterior part of the right auricle, where it was still 
moist, and by increasing the stimulus, stronger contractions resulted. 
At 11.33 the same results were obtained on stimulating the left 
auricle. 
At 11.28, and again at 11.40, stimulation produced only fibrillary 
contraction. 
At 11.44, on stimulating strongly the upper and inner part of the 
right auricle, a strong contraction resulted, with a peculiar tetanic 
appearance of the muscle along the line of stimulation. This part, as 
compared with the other parts, which had previously failed to 
