THE PRINCIPLE OF VITAL AFFINITY: 337 



living animals. It is by thus losing their vitality that these molecules become 

 liable to the interstitial absorption (of Huntee) ; and their places are taken by 

 fresh molecules by virtue of the vital attraction which constitutes nutrition. 



It appears certain also, that the healthy exercise of the vital functions of any 

 texture (although within certain limits it strengthens aU the vital properties, and 

 augments the living structure, apparently by attracting an increased flow of blood) 

 determines the more speedy death of the molecules composing it, and the more 

 rapid change of its particles by absorption. This may be expressed by saying, 

 that this mode of vital action, as well as all muscular and nervous action, is sub- 

 ject to the general law of alternate increase and diminution. Hence the in- 

 crease of absorption, and therefore of the excretions from exercise, even when 

 all ingesta have ceased. And hence, also, if the vital act of nutrition in any tex- 

 ture is morbidly excited, as happens in every case of inflammation tending to the 

 formation of plastic lymph, we have subsequently an increased loss of vitality 

 in the molecules of that part ; and therefore, either the formation of purulent 

 matter destined to excretion, or the increased absorption of the newly formed 

 or effused lymph, or the ulcerative absorption of the solids previously existing, 

 or sloughing, or gangrene,— all well-known results of the inflammation, but which 

 have not been duly regarded as all implying more or less partial loss of vitality, 

 and therefore dependent on the same principle ; and which experience shews to 

 be linked together and even to graduate into one another. 



In like manner the progressive absorption of Hunter is probably to be ascribed 

 to the influence of pressure, injuring and permanently destroying the vitality of 

 parts not intended nor fitted to imdergo pressure, and thereby preparing them for 

 absorption and for the action of oxygen. 



It is hardly necessary to add to this statement, after the researches of Dulong 

 and Despeetz, of Dumas and of Liebig, that the combination of oxygen with 

 the other constituents of the excretions, and particularly with the carbon and 

 hydrogen, is (as has always been maintained by most physiologists in this coun- 

 try) the true cause of Animal Heat ; and it cannot be doubted that one of the 

 uses of the aliments, especially the non-azotised aliments, continually taken into 

 the body, is merely to enter into this combination, and fulfil this purpose. But 

 there is one principle on this subject, not so generally recognised, but which the 

 observations of Liebig, and likewise of Scherer, of Pettenhoffer, and of 

 BoucHARDAT and Sandras,* seem to make nearly certain, viz., that a principal 

 use of the secretion of the Liver {i. e. of the animal matter there secreted) is, to 

 serve as a reservoir for the most easily combustible matter which is taken into 

 the primse vise ; so that, — just as the chyme of the stomach and intestines fur- 

 nish a pretty constant supply of nourishment from occasional supplies of ahment, — 



* See Paget's Report in Forbes's Journal, April 1846, pp. 561 and 562. 

 VOL. XVI. PART III. 4 Q 



