VARYING ACTIVITY OF THE NUTRITIVE PROCESSES. 5S9 



by Inflammation tend to contract, and thus to press upon the vascular struc- 

 ture, which frequently happens in the lungs, liver, and kidneys ; or when the 

 inflammation occurs in the vessels themselves, causing adhesion of their walls, 

 and obliteration of their tubes ; or when a new growth absorbs into itself all 

 the nutritive materials which the Blood supplies.* 



792. The nutritive operations take place, with extraordinary energy and 

 rapidity, in the process of Reparation ; by which losses of substance, occa- 

 sioned by injury or disease, are made good. In its most perfect form, this 

 process is exactly analogous to that of \\\& first development of the correspond- 

 ing parts ; and its results are as complete in the one case as in the other. In 

 fact, among the lowest tribes of Animals, we find these two conditions 

 blended, as it were, together; for the process of reparation may be carried in 

 them to such an extent, as to regenerate the whole organism from a very small 

 portion of it. In the Hydra, or Fresh-water Polype, there would seem to be 

 scarcely any limit to this power; for, if the body of the animal be minced 

 into the smallest possible fragments, every one of these can produce a new 

 and perfect being. In this manner no less than forty have been artificially 

 generated from a single individual. In ascending the Animal scale, we find 

 this reparative power less conspicuous, because exercised with regard to 

 smaller parts only of the body ; but the greater complexity of the changes 

 involved in the process, renders it in reality not less considerable than in the 

 lower classes. Thus, the restoration of a Bone destroyed by Necrosis is a 

 much more extraordinary operation, than the growth of an entire Polype from 

 a single fragment; since it involves a far greater amount and variety of 

 actions. Numerous and well-authenticated instances are on record, of the 

 reunion of parts that had been entirely separated from the body, and of the 

 restoration of all their vital properties : and this could only take place, through 

 the perfect reproduction of a large number of very different structures. The 

 reappearance of Fungous growths, whose organization is of a low character, 

 is a fact with which every surgeon is familiar ; and cases occasionally, though 

 rarely, present themselves, in which reproduction of a whole member takes 

 place even in the Human subject.! 



793. It is the general opinion among British surgeons (founded upon what 

 they believe, but erroneously, to have been the doctrine of Hunter), that In- 

 flammation is essential to the process of Reparation. There is no doubt that, 

 as usually conducted, the healing of wounds is attended by a greater or less 

 degree of Inflammation ; but it does not thence follow that this morbid con- 

 dition is essential to the renewal of the healthy state ; and in fact it can be 

 shown that, in the majority of cases, the Inflammation is injurious rather than 

 beneficial. The following important conclusions are drawn by Dr. Macart- 

 ney:]: from a very philosophical comparative survey of the operations of Re- 

 paration and Inflammation, as performed in the different classes of animals : 

 " That the powers of Reparation and Reproduction are in proportion to the 

 indisposition or incapacity for Inflammation ; that Inflammation is so far 

 from being necessary to the Reparation of parts, that, in proportion as it exists, 

 the latter is impeded, retarded, or prevented; that, when Inflammation does 

 not exist, the Reparative power is equal to the original tendency to produce 

 and maintain organic form and structure ; and that it then becomes a natural 

 function, like the growth of the individual, or the reproduction of the species." 

 794. Guided chiefly by Dr. Macartney's views, which have derived im- 



* See on this subject Dr. Williams' Elements of Medicine, chap. iv. ; to which the Author 

 is partly indebted for the preceding paragraphs. 



f See, on the whole of the subject of the comparative powers of Reparation in the Ani- 

 mal series, the Author's Principles of Gen. and Comp. Physiol. 586, 587. 



J Treatise on Inflammation, p. 7. 



