‘ 
PHYSICAL anv LITERARY. 317 
ricle fhewed, at confiderable intervals, a 
very faint pulfation; but the heart lay 
without any motion. 
g- THe fame day, after cutting off the 
head and deftroying the {pinal marrow of 
another frog, | laid bare its abdominal 
mufcles and ¢horax ; and, at eighteen. mi- 
nutes paft ten, immerfed it ina folution 
of opium, asabove. Eighteen minutes 
paft eleven, I took it out of the folution 
and opened its thorax and pericardium, after 
which the heart began to move at the rate 
of 8 times ina minute. Twenty five mi- 
nutes pat eleven, the heart beat. 15 times 
in a minute; and at twelve o'clock it per- 
formed between 13 and 14 vibrations in the 
fame time. At two o'clock, (viz. two 
hours and forty two minutes after the 
frog was.taken out of the folution) the 
auricle, which was now filled with air, 
continued to vibrate weakly, about r4 
times in the minute; but the heart irfelf 
was without motion, Ar ten minutes be- 
fore four in the afternoon, the auricle full 
continued to move, bur more feebly than 
the auricle of N° 5. 
1o, I 
