478 PHILOSOPHICAL TRANSACTIONS. [aNNO I67O. 



live either without any, or without a full respiration, would not be more 

 difficultly or slowly killed by the want of the air, than others, which had been 

 longer used to a free respiration; we took a kitling that had been kittened the 

 day before, and put it into a very small receiver (which we guessed to hold 

 about a pint or less) that it might be the sooner exhausted. As soon as the 

 pump began to play, I took notice of the time, and found by a watch, that 

 within one minute or a little more after the air first began to be withdrawn, the 

 little animal, who in the mean time had gasped for life, and had some violent 

 convulsions, lay as if dead, with his head downwards, and his tongue out ; but 

 upon letting in .of the air, he immediately showe'd signs of life, and being taken 

 out of the receiver quickly recovered : And to allow him the benefit of his good 

 fortune, we sent for a kitling of the same age and litter, which being put into 

 the same receiver, quickly began, like the other, to have convulsions, after 

 which he lay as dead ; but observing very narrowly, I perceived some little 

 motions, which made me conclude him alive, in which I was not mistaken. 

 For though we continued pumping, and could not perceive that the engine 

 leaked more than in the former experiments ; the kitling began to stir again, 

 and after a while had stronger and more general convulsions than before ; till at 

 the end of full six minutes after the exsuction of the air was begun, the animal 

 seeming quite dead, the outward air was readmitted into the receiver, which 

 not reviving him as it had done the other, he was taken out of the vessel, and 

 lay with his mouth open, and his tongue lolling out without any sensible 

 breathing and pulsation; till having ordered him to be pinched, the pain or 

 some internal motion, produced by the external violence, made him immediately 

 give manifest signs of life, though there was yet no sensible motion of the 

 heart or the lungs; but afterwards gaping and fetching his breath in an 

 odd manner, and with much straining, as I have seen some foetuses do, when 

 cut out of the womb, he little by little, within about a quarter of an hour, re- 

 covered: wherefore thinking it severe to make him undergo the same measure 

 again, we sent for another, kittened at the same time, and inclosing that also 

 in the receiver, observed that divers violent convulsions, as it were gasping for 

 breath, into which he began to fall at the second or third suck, ended in a 

 seeming death, within about a minute and a half. But being made more diffident 

 by the late experiments, I caused the pump to be plied, the rather, because I 

 had a mind to observe whether, when the air was from time to time drawn 

 away, there would not, upon the opening of the stop-cock to let it out, ap- 

 pear some sudden swelling of the body of the animal, by the spring and ex- 

 pansion of some air (or aerial matter) included in the thorax, or the abdomen.; 

 Such an inflation, though not great, we thought we observed; but till further 



