PHYSICAL AND LITERARY. 291. 



paft twelve, (i. e. an hour and nine minutes, 

 after the frog was taken out of the folution) 

 its heart made only 6 pulfations in the mi- 

 nute i and at eleven minutes paft twelve, 

 obferving it without motion, I pricked it 

 with a pin, and breathed upon it, in order to 

 renew its pulfation, but to no purpofe. 



II. Twenty eight minutes paft feven in 

 the evening, I laid open the whole abdomen 

 and thorax of a frog, and immediately after 

 imm^rfed it in a folution of opium as above. 

 Thirty eight minutes paft feven, when I prick- 

 ed its legs with the point of a penknife, it 

 made very little motion, Two minutes after 

 this, I turned it to its back, and obferved its 

 heart moving only between ten and eleven 

 times in. a minute, . .Having laid the frog a- 

 gain on its belly, that it might be more ex- 

 pofed to the action of the opiuni ; at forty 

 eight minutes paft feven, i. e, twenty minutei 

 from the firft immerfion, I turned it again 

 to its back, and obferving the heart without 

 motion, I opened the pericardium j which 

 producing no effect, I cut the heart out of 

 the body, and laid it on a plate, when it 

 gave two or three pulfes, apd never after 



moved, 



