EXTRACT XVII. 



ON THE OCCURRENCE OF VACUA IN THE ORGANIC, 

 OR METABOLIC, WORK OF THE HUMAN BODY, 

 AND ON "SUCTION" EVACUATION, AND GRAVI- 

 TATION, IN RELATION THERETO, OR THE DYNA- 

 MICS OF CIRCULATION. 



THE existence of an absolute vacuum is an impossibility, 

 in the everyday working of the human, and every other 

 organic, body, and is only thinkable as a scientific curiosity, 

 the existence, however, of comparative vacua throughout 

 nature, is not only thinkable, but constantly observable in 

 that portion of it within our reach. 



Thus, the earliest indications in the human infant of its 

 power of self-existence are the creation, by reflex neuro- 

 muscular effort, of an uncountable multitude of vacua, in 

 its hitherto unopened, or pseudo-impervious, pulmonary 

 parenchyma, in virtue of which an inrush of atmospheric 

 air commences the life-long process of breathing, with all 

 that is dependent thereon of functional and material 

 change and organic work next to death, this is one of 

 the most marvellous, and important, changes, effected in 

 the history of fceto-infantile evolution, marking, as it 

 does, the beginning of separate and independent existence, 

 the commencement of individual life, and the perpetuation 

 of the species. 



The vacua created here, in embryonically prepared 

 structures, are effective, till the termination of the indi- 

 vidual existence, and by rhythmic repetitions of the original 

 respiratory movement, in maintaining the union between 

 the body, and what constitutes the hitherto inexplicable 



