482 DR KNOX on the Structure of the Stomach 



But he is bound to do this cautiously, inasmuch as analogies 

 are deceitful, and previous experience and observation fruitless, 

 when it attempts to bind down to fixed laws and permanent 

 forms, structures which, in the hands of an all-powerful Agent, 

 seem, on most occasions, to be made subservient to function, 

 and are changed and altered, or, as the physiological phrase goes, 

 modified and diversified, to an extent harassing to the mind of 

 the impatient inquirer, and puzzling to all. 



To obviate certain of these difficulties, the anatomical in- 

 quirer resorts to other sources of knowledge, to other means, in 

 order to come at the desired object. He patiently observes the 

 habits of animals ; the effects of climate and of domestication ; 

 the kind of food seemingly enjoined them by Nature ; in short, 

 their natural history ; and, aided by this, he again returns to his 

 previous anatomical investigation, hoping confidently to verify 

 in the body deprived of life the truth of the observations he had 

 made on the living ; and, by comparing what he already knows 

 of function with what he sees of structure, to decide on cause 

 and effect ; give reasons for absence, alteration, or modification of 

 parts ; in a word, to solve the difficult problem of the uses of the 

 parts in animal bodies *. 



In this complicated and extended inquiry, which has endured 

 now so many thousand years, it has not unfrequently happened, 

 that the most experienced observers in the field of inquiry have 

 forgot the sources of their knowledge, when they fancied them- 

 selves in possession of laws conclusive as to animal structure ; 



* The presence of certain generative organs in the male and female, and of the 

 hyoid bones, in the Mammalia, together with nearly all rudimentary organs, in- 

 cluding the swimming-bladder of fishes, urinary bladder in the same animals, &c. 

 have hitherto defied the attempts of all anatomists to explain. Mr HUNTER said that 

 " Nature was fond of analogy ;" and so, I presume, in sport, placed organs in ani- 

 mals which seemingly performed no functions ; but these explanations will not pass 

 current now, I presume, with any one who pretends to any physiological judgment. 



