MARIE FRANgOIS XAVIER BICHAT 173 

 the peritoneum, for example, enters or does not enter, into the gastric 

 viscera, according to their fulness or vacuity. 



Shall I speak of the pectoral organs? What has the life of the 

 fleshy texture of the heart in common with that of the membrane 

 that surrounds it? Is not the pleura independent of the pulmonary 

 texture? Has this texture nothing in common with the membrane 

 that surrounds the bronchia ? Is it not the same with the brain with 

 relation to its membranes, of the different parts of the eye, the ear, 

 etc.? 



When we study a function it is necessary carefully to consider in a 

 general manner, the compound organ that performs it ; but when you 

 wish to know the properties and life of this organ, it is absolutely 

 necessary to decompose it. In the same way, if you seek only general 

 notions of anatomy, you can study each organ as a whole; but it is 

 essential to separate the textures, if you have a desire to analyze with 

 accuracy its intimate structure. 



CONSEQUENCES OF THE PRECEDING PRINCIPLES RELATIVE 



TO DISEASE 



What I have been saying leads to important consequences, as it re- 

 spects those acute or chronic diseases that are local ; for those which, 

 like most fevers, affect almost simultaneously every part, cannot be 

 much elucidated by the anatomy of systems. The first then will en- 

 gage our attention. 



Since diseases are only alterations of the vital properties, and each 

 texture differs from the others in its properties, it is evident that there 

 must be a difference also in the diseases. In every organ, then, com- 

 posed of different textures, one may be diseased, while the others re- 

 main sound ; now this happens in a great many cases ; let us take the 

 principal organs, for example. 



1st. Nothing is more rare than affections of the mass of the brain ; 

 nothing is more common than inflammation of the tunica arachnoid es 

 that covers it. 2d. Oftentimes one membrane of the eye only is af- 

 fected, the others preserving their ordinary degree of vitality. 3d. In 

 convulsions or paralysis of the muscles of the larynx, the mucous sur- 

 face is unaffected ; and on the other hand, the muscles perform their 

 functions as usual in catarrhs of this surface. Both these affections 



