OF NATURAL HISTORY. 129 



fions. Through thefe fiffures and vacuities the eggs of toads may 

 accidentally be conveyed by water, the penetration of which few 

 fubftances are capable of refifting. After the eggs are hatched, the 

 animals may receive moifture, and fmall portions of air, through 

 the crevices of rocks, or. the channels of aged trees. But I mean 

 not to perfuade ; for I cannot fatisfy myfelf. All I intend is to re- 

 commend, to thofe gentlemen who may hereafter chance to fee fuch 

 rare phaenomena, a ftridt examination of every circumftance that 

 can throw light upon a fubjedl fo dark and myfterious ; for the vul- 

 gar, ever inclined to render uncommon appearances ftill more mar- 

 vellous, are not to be trufted. 



From the fads 1 have enumerated, it is apparent that air, in cer- 

 tain proportions, according to the ftrudure and conftitution of every 

 animated being of which we have any knowledge, is indifpenfibly ne- 

 ceflary for the exiftence and continuation of animal life. Not only 

 men, quadrupeds, birds, fifhes, reptiles, and the larger infedts, but even 

 fleas, mites, the minute eels found in pafte or in vinegar, and the ani- 

 malcules produced by infufing animal or vegetable fubftances in wa- 

 ter, inevitably perifli when deprived of this all-vivifying element. 



With regard to plants, air is fo necefTary to their exiftence, that 

 they do not vegetate in an exhaufted receiver. Plants, as formerly 

 mentioned, are furnifhed with numerous air-vefTels, or refpiratory 

 organs. They abforb and tranfmit air through every pore. When 

 placed in an exhaufted receiver, the air contained in every part of 

 their fubftance is foon extracted; and, in proportion as this air is 

 llkewife pumped out by the machine, the flowers and leaves fhow 

 evident fymptoms of debility; they become flaccid, pendulous, and 

 affume a fickly appearance ; and, if retained in that fituation a cer- 

 tain length of time, their vegetating powers are irrecoverably ex- 

 tinguiflied. 



T R Upon 



