VOL. v.] PHILOSOPHICAL TRANSACTIONS. 48/ 



sufficient number of instances is to be met with among our other experiments, 

 and therefore I shall now subjoin more trials respecting the former, because 

 this comparison has not, that I know of, been yet thought on by any. 



Exp. I. — Sept. 10. A greenfinch, having his legs and wings tied to a weight, 

 was gently let down into a glass body filled with water; the time of its total im- 

 mersion being marked : at the end of half a minute after that time the strug- 

 glirigs of the bird seeming finished, he was nimbly drawn up again, but found 

 quite dead. 



Exp. II. — ^Whereupon a sparrow, that was very lusty and quarrelsome, was 

 tied to the same weight, and let down after the same manner ; but though he 

 seemed to be, under water, more vigorous than the other bird, and continued 

 struggling almost to the very end of half a minute from the time of his being 

 totally immersed (during which stay under water there ascended, from time to 

 time, pretty large bubbles from his mouth,) yet, notwithstanding that as soon 

 as ever the half minute was completed he was drawn up, we found him, to 

 our wonder, irrecoverably gone. 



Exp. III. — ^A small mouse being held under water by the tail, emitted from 

 time to time divers aerial bubbles out of his mouth, and at the last also at 

 one of his eyes ; being taken out at the end of half a minute and some few 

 seconds, he yet retained some motions ; but they proved convulsive ones, 

 which at last ended in death. 



By what is related under the First Title, it does not appear that water-fowl, 

 at least that ducks, could in our receivers endure the want of air much longer 

 than other birds : but now, to show that the contrivance of nature is not in- 

 significant, as to the enabling them to continue much longer under water, 

 without fresh air, than the land birds above-mentioned, it will not be amiss to 

 subjoin the two following experiments. 



Exp. IV. — ^We took the duck mentioned in the First Title, and tied a con- 

 siderable weight of lead to her body, in such a manner as not to hinder her 

 respiration, and yet to keep her down under water. With the above-mentioned 

 clog, the duck was put into a tub full of clear water, under whose surface she 

 continued about a minute by my watch, quietly enough, but afterwards began 

 to appear for a while disturbed ; which fit being over, our not perceiving any 

 motion in her made us, at the end of the second minute, take her out of the 

 water, to see in what condition she was, and finding her in a good one, after 

 we had allowed her some time to recruit herself with fresh air, we let her down 

 again into the tub, which in the mean time had been filled with fresh water, 

 lest the other, which had been troubled with the steams and foulness of the 



