VOL. v.] PHILOSOPHICAL TRANSACTIONS. 511 



all of them very small) not much differing in size. From all of these save one 

 we withdrew the air, and then making use of our peculiar contrivance to hinder 

 its return, we took them one after another from the engine, and laid them by 

 for further observation. That one, which I took notice that we had reserved, 

 and in which, to observe the difference, we thought fit to leave the air, was 

 sealed at a lamp furnace, after the usual manner of nipping up glasses there. 

 Tliis done, there remained nothing but to observe the event of our trials, which 

 afforded us the ensuing phaenomena. 



1. Those mites that were inclosed in the small glass that never came near the 

 engine, continued alive and able to walk up and down for above a full week 

 after they had been put in, and possibly would have continued much longer, if 

 the glass had not been accidentally broken. 



2. As soon as ever one of the receivers was removed from the engine, I 

 looked with great attention upon it ; and though just before the withdrawing of 

 the air the mites were seen to move up and down in it; yet within a few mi- 

 nutes after the receiver was applied to the engine, I could discern in them no 

 life at all, nor was any perceived by some younger eyes than mine, whereunto 

 I exposed them. Nay by the help of a double convex glass (that was so set in 

 a frame as to serve me as a microscope on such occasions) I was not able to see 

 any of them stir up and down. Nor was any motion taken notice of in the 

 other small receiver of like size and shape with mine, by them that had ex- 

 hausted it of air. And my occupations not permitting me to attend the observa- 

 tion any longer in the place where it was made, I took the receiver, I had so 

 attentively considered myself, along with me in the coach, and having occasion 

 to make some stay, about an hour after I looked upon it attentively again, but 

 could not perceive any of the mites stir; and the like unsuccessful observation I 

 made when I had an opportunity two or three hours after that. And the place 

 I did it in being one where I thought myself as it were at home, I first let in 

 the air to try if the mites were not quite dead, and though neither upon its 

 rushing in, nor during my stay there, I could perceive any of them to stir, yet 

 I left the receiver unstopped as it was in the window, upon a suspicion that the 

 air might not be able to produce its operation upon them in a short time. 



3. And therefore passing by the same place about two or three days after, I 

 called in to look upon my receiver, and found a number of my little animals re- 

 vived, as an attentive eye might easily perceive by the motion of certain little 

 white specks, when it was helped to observe it by little marks I made on the 

 outside of the glass (which was purposely chosen thin and clear) near this or that 

 mite with a diamond ; by the approach to or recess from which marks the pro- 

 gressive motion became (perhaps within a minute) plainly discoverable, especi- 



