452 OF NUTRITION. 



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 fami- 

 liar; and cases occasionally, though rarely, present themselves, in which re- 

 production of a whole member takes' place even in the Human subject.* 



594. Before proceeding to describe in detail the mode in which the primor- 

 dial cells are converted into the several varieties of tissue, it may be desirable 

 to take a general survey of the conditions under which the reparative processes 

 are carried on, a question of great practical importance, on which very mis- 

 taken notions are prevalent. It is a general opinion among British surgeons, 

 (founded upon what they believe, but erroneously, to have been the doctrine of 

 Hunter), that inflammation is essential to the process of reparation. There is 

 no doubt that, as generally conducted, the healing of wounds is attended by a 

 greater or less degree of inflammation ; but it does not thence follow that this 

 morbid condition 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. Ma- 

 cartneyt from a very philosophical comparative survey of the operations of 

 reparation 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 func- 

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



595. Guided chiefly by Dr. Macartney's views, which have derived impor- 

 tant confirmation from recent observations, we shall treat of the reparative pro- 

 cesses under three distinct heads : First, the adhesion of the sides of a wound 

 by a medium of coagulable lymph, or of a clot of blood. Second, reparation 

 without any medium of lymph or granulations, the cavity of the wound being 

 filled by a natural process o/ growth from its walls. Third, reparation by 

 means of a new, vascular, and organized substance, termed granulations. The 

 first of these modes of reparation, is that which is ordinarily termed union by 

 the first intention; of this kind of adhesion, the 'healing of the incision made 

 in venesection, which usually takes place almost without consciousness on the 

 part of the patient, and with scarcely any inflammation, is a characteristic ex- 

 ample : the white line of cicatrix which is left, marks the formation of new 

 substance, and is the result of the want of that perfect approximation of the 

 lips of the wound, which may frequently be obtained in parts where pressure 



* See, on the whole of the subject of the comparative powers of Reparation in the 

 Animal series, the Author's Principles of Gen. and Com. Physiol. 586, 587. 

 j- Treatise on Inflammation, p. 7. 



