ORIGIN OF THE SOLID TISSUES. 603 



seem in particular cases to be equally effectual. To Dr. Greenhow, of New- 

 castle, for instance, it was accidentally suggested, a few years since,* to cover 

 the surface of recent burns with a liquefied resinous ointment; and he states 

 that in this manner Suppuration may be prevented, even where large sloughs 

 are formed; the hollow being gradually filled up by new tissue, which is so 

 like that which has been destroyed, that no change in the surface manifests 

 itself, and none of that contraction, which ordinarily occurs even under the 

 best management, subsequently takes place. A plan has, moreover, been 

 proposed for preventing suppuration, and promoting reparation by the model- 

 ling process, which consists in the application of ivarm dry air to the wounded 

 surface. The experiments made on this have not been entirely satisfactory, 

 but they seem to show that, though the process of healing is much slower 

 under treatment of this kind, it is attended with less constitutional disturb- 

 ance than is unavoidable in the ordinary method; and it may, therefore, be 

 advantageously put in practice in those cases in which the condition of the 

 patient requires every precaution against such an additional burthen, as after 

 amputation in a strumous subject. But of the superiority of this treatment 

 to the water-dressing, no evidence has yet been adduced. 



799. The third method of Reparation, that by Granulation appears to 

 be a means employed by Nature for the purpose, under the unfavourable cir- 

 cumstances of Irritation or a continuance of Inflammation; proving that parts 

 previously in a healthy state, are disposed to heal, in despite of many impe- 

 diments thrown in their way. The Granulation-structure is a special one, 

 formed for a temporary purpose. It is endowed with higher vascularity and 

 a more rapid power of growth, than is possessed by any modification of 

 ordinary tissue; but it is very easily destroyed by injury, or by a higher 

 degree of inflammation. The existence of Granulations has been supposed 

 to be necessary to fill up deficiencies; this, however, is not altogether true; 

 as we occasionally find very considerable vacancies filled with lymph, which 

 gradually becomes organized, without being converted into granulations; and 

 the void may be also supplied by the process of natural growth just described. 

 Moreover, it is only in the beginning that granulations take the place of the 

 natural structure; for the approximation of the edges of a wound filled with 

 them, requires that they should be removed by interstitial absorption; so that 

 wounds healed by this process do not exhibit any remains of the new me- 

 dium. This approximation somewhat resembles that which occurs in open 

 wounds that have never inflamed, being the result of the natural processes of 

 growth; and it does not take place until the Inflammation has in great degree 

 subsided : but it differs from the modelling processes in this, that, as the wound 

 is occupied by granulations, its closure takes place prematurely, as it were ; 

 so that, when the granulations are subsequently absorbed altogether, a con- 

 tracted cicatrix is the result. It will be presently seen that the formation of 

 the Granulation-structure is intimately connected with the elaboration of Pus ; 

 and this process, accompanied as it is with such great constitutional disturb- 

 ance, and involving such a loss of nutritious material, cannot but be regarded 

 as an action to be altogether avoided, if possible. 



800. We shall now consider, more in detail, the nature of the process of 

 Granulation, and of the Suppuration which usually accompanies it. Its com- 

 mencement is exactly conformable to the first stage of ordinary reunion by the 

 first intention ; for Liquor Sanguinis is thrown out, in which Exudation-cor- 

 puscles present themselves in large numbers. According to Gerber, the trans- 

 formation of these into a sort of imperfect Epithelium may be seen to take 

 place within half an hour. New layers are in the mean time developed ; and 



* Medical Gazette, Oct. 13, 1838. 



