Food. .301 



hillierto been done in the way of chemical analysif?^ must go for no- 

 thing, inasmuch as such attempts have been thrown away upon the 

 examination of other secretions, such as saliva, bile, and mucus, 

 which are to be met with in the stomach. 



Thus, some philosophers have maintained that the gastric juice is 

 an acid, and others that it is an alkali. But if we may trust to the 

 conclusions of the ingenious Spallanzani, the gastric juice is, natu- 

 rally, neither acid nor alkaline. 



If it be poured on carbonate of potash, it occasions no efferves- 

 cence ; and upon the whole, we may safely say, that no certain 

 conclusions can be drawn from any experiments hitherto made by 

 philosophers, respecting the chemical nature of the gastric juice. 



But, though I think it highly probable tliat the utmost efforts of 

 human skill and labour, will never lead nearer to a comprehension of 

 the actual mode in which digestion is effected, than that point, which 

 we have been permitted to approach, in our attempts to investigate 

 many of the impenetrable mysteries of nature ; I confess, for my own 

 part, I see no cause for regret, on this score. 



For, whilst the line appears to be drawn by the author of nature, 

 for wise and inscrutable purposes, beyond which our most laborious 

 investigations cannot possibly go, yet, the objects aimed at, in the 

 course of these enquiries, not only serve to ennoble the pursuits of 

 philosophy, and to enrich the stores of science, btft to develope 

 some things, which are found to be strictly applicable to practical 

 purposes. 



The truth is, that some very curious and important facts have 

 been biought to hght, in consequence of the experiments made on 



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