( 40 ) 



and regain'd her feet, and, in about a quarter of an hour after, attempted to escape 

 at the top of the glass, which had been unstop'd to let in the air upon her : but the 

 receiver being closed the second time, she died violently convuls'd, within five minutes 

 from the first stroke of the pump. 



"Then we put in a mouse, newly caught, and, whilst he was leaping up very high in 

 the receiver, we fasten'd the cover to it; expecting, that an animal, used to live with very 

 little fresh air, would endure the want of it better than the birds ; but tho', for a while 

 after the pump was set on work, he continued leaping up, as before ; yet 'twas not long 

 ere he began to appear sick, giddy, and to stagger ; after which, he fell down as dead, 

 but without such violent convulsions as the birds had : when, hastily letting in some 

 fresh air upon him, he recover'd his senses, and his feet, but seem'd to continue weak and 

 sick ; at length, growing able to skip as formerly, the pump was ply'd again, for eight 

 minutes ; about the middle of which space, a very little air, by mischance, got in at 

 the stop-cock ; and, about two minutes after that, the mouse, several times, leap'd up 

 lively ; tho', in two minutes more, he fell down quite dead ; yet with convulsions far 

 milder than those wherewith the birds expired. This alacrity, so little before his death, 

 and his not dying sooner than at the end of the eighth minute, seem'd owing to the air 

 that pass'd into the receiver ; for, the first time, the convulsions seiz'd him, in six minutes 

 after the pump began to be work'd. These experiments seemed the more strange, 

 because during a great part of those few minutes, the engine could but considerably rarify 

 the air, and that too by degrees ; and, at the end thereof, there remained in the receiver 

 a large quantity ; for, as we formerly said, we could not draw down water in a tube, 

 within much less than a foot of the bottom. And, by the exsuction of the air, and inter- 

 spersed vacuities, there was left in the receiver a space some hundreds of times exceeding 

 the magnitude of the animal, to receive the fuliginous steams, from which, expiration 

 discharges the lungs, and which, in the other cases, may be suspected, for want of room 

 to stifle those animals that are closely pent up in too narrow receptacles." (Collected Work 

 of the Hon. R. Boyle, by Peter Shaw, M.D., vol. II., p. 461, 1725.) 



\ SINGULARLY able man was ROBERT HOOKE (1635-1703), 



\ a born experimentalist and accurate observer, who made 



another advance in the physiology of respiration possible. 



Hooke was assistant to Boyle, and when the Royal Society was 



founded he was appointed Curator of Experiments. In his 



ORIGINAL FIGURE OF HOOKE's COMPOUND MICROSCOPE. 



