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^. On the Nature of Death. % A. P. W. Philip, 7I/.D. F.R.S. L. i^ E. i^c. 



Received October 25, 1833,— Read February 13 and 20, 1834. 



1 NEED hardly say, that in such a communication as the present, I have no inten- 

 tion of entering into the part of the subject of this paper which may justly be termed 

 metaphysical. The veil which separates it from experimental science must ever 

 remain impenetrable, there being no source of information respecting it, but a direct 

 revelation from the great Author of our being, or the instincts he has implanted in our 

 nature, for all knowledge is not acquired. We come into the world with knowledge 

 essential to our existence. The infant knows as well how to breathe and how to suck 

 as the adult, and these acts depend as much on mental operations as those which are 

 the results of experience. He perceives his wants, and he knows how to relieve them ; 

 and the extent to which this species of knowledge exists in some animals, whose rea- 

 soning powers are extremely limited, justly excites our wonder and admiration. They 

 know what is essential to their condition with an accuracy which sets at defiance all 

 the efforts of human reasoning, for their knowledge is the knowledge of their Creator. 



To the physiological part of the subject alone I wish to direct the attention of the 

 Society. It forms part of the same subject with the three last papers I had the honour 

 to present to it, published in the Philosophical Transactions for 1831 and 1833; 

 namely, the relation which the different powers of the living animal body bear to each 

 other. In these papers I endeavoured to trace the nature of their influence on each 

 other while their state of vigour remains ; in the following paper I shall attempt to 

 point out the manner in which they influence each other in their state of decay. 



In the course of my Inquiry into the Laws of the Vital Functions, it became necessary 

 to determine, with more precision than had been done, the line of distinction between 

 the sensorial and nervous functions. 



The function of the muscular system, from its nature and the peculiar structure of 

 its organs, is readily defined ; but in the nervous system we perceive more than one 

 set of functions, and yet, both from the variety of ways in which they are interwoven, 

 and from the peculiar mechanism of the active parts of their organs being so minute 

 as to escape our senses and consequently the investigations of the anatomist, the 

 difficulty of correctly distinguishing them is considerable. It is only by experiments 

 instituted for the purpose, and founded on the very different nature of these sets of 

 functions, that the line of distinction can be drawn. 



In order to render the results more certain, I endeavoured to ascertain this line by 

 two sets of experiments, conducted on different principles ; the object of the one being 



