NATURAL THEOLOGY. 91 



the gastric juice acts, we may be able to ascertain 

 the chemical principles upon which its efficacy 

 depends, as well as from what part, and by what 

 concoction, in the human body these principles 

 are generated and derived. 



In the mean time, ought that, which is in truth 

 the defect of our chemistry, to hinder us from ac- 

 quiescing in the inference which a production of 

 nature, by its place, its properties, its action, its 

 surprising efficacy, its invaluable use, authorizes 

 us to draw in respect of a creative design P^ 



Another most subtle and curious function of 

 animal bodies is secretion. This function is semi- 

 chemical and semi-mechanical ; exceedingly im- 

 portant and diversified in its effects, but obscure 

 in its process and in its apparatus. The import- 

 ance of the secretory organs is but too well attest- 

 ed by the diseases which an excessive, a deficient, 

 or a vitiated secretion is almost sure of producing. 



23 After this enumeration of the things dissolved by the gastric 

 juice, the most extraordinary fact remains to be stated, that the 

 dehcate surface of the stomach itself, softer and finer than the 

 surface of the eye, remains untouched by this humour, which our 

 autlior, somewhat quaintly, describes as more powerful to dissolve 

 than aqua-fortis. John Hunter showed us that it was the property 

 of life that protected the coats of the stomach. This fact is a most 

 singular proof of the power bestowed through life on the mem- 

 branes and vessels ; and it is as important as it is curious : for as 

 the stomach in the dead body no longer resists this menstrum, it 

 may become dissolved, if the person has died with the fluid 

 already secreted into the stomach. And so it has happened that 

 persons have been supposed to be poisoned, and relations have 

 been falsely accused, from the stomach being found eroded as if 

 some acrid poison had been taken before death. 



