OF TREATMENT IN SURGERY 83 



a piece of tin is a novel mode of healing by scabbing. But tlie ordinary scab 

 is in so far analogous to the metallic plate, that the exudations of which it is 

 composed having dried before they had time to putrefy, the crust is, like the 

 metal, a neutral or unstimulating solid. Further, there is putrescible moisture 

 beneath the scab as beneath the tin ; but the mode in which the putrefactive 

 organisms are excluded is essentially different. The scab keeps them out 

 mechanically, by adhering firmly to the surface of the integument ; the metallic 

 plate opposes no mechanical barrier to their entrance, but is guarded by a germ 

 poison in the surrounding lac which no less imperatively forbids their access. 



Altogether the case must be regarded as affording great encouragement 

 for giving a further trial to this method, which seems to bring the treatment of 

 compound fracture to something nearly approaching perfection. The lac, being 

 impermeable to discharge, combines the properties of an external antiseptic 

 guard wdth those of a permanent crust ; and, as fresh carbolic acid can be 

 supplied to it as often as may be desired without disturbing its position, the 

 trouble and risk that attended the changing of the putty are entirely got rid of. 

 At the same time the tin protects the raw surface from the acid with absolute 

 certainty, while the tin and the lac constitute together so thin a layer as not 

 to alter the contour of the limb, or interfere with the shape of splints such as 

 would be used for simple fracture ; a considerable advantage as compared with 

 the mass constituted b}^ a thick crust, covered with substantial putty. When 

 the wound is large, I would advise the use of two layers of the lac-plaster for 

 the sake of additional strength, the outer one overlapping the inner by an inch 

 or two ; and the outer, like the inner, rendered adhesive, as above described, 

 so that the two may become incorporated into one mass. Also, I would recom- 

 mend that, as was done in the second dressing of the last case, the film of gutta- 

 percha should be left upon a track leading from the tin to what is to be the most 

 dependent part of the edge of the plaster to afford free egress for sero-sanguineous 

 discharge. 



For treating the interior of the wound in compound fracture, I employed, 

 till comparatively lately, the undiluted acid, and, as this afforded excellent 

 results, I did not venture to change the practice without having some more 

 substantial basis than hope to found upon. But rather more than a year ago, 

 having observed that the injection of a saturated watery solution (one part 

 of acid to twenty parts of water) among the fibrous tissues in a fetid suppurat- 

 ing wound of the palm, completely arrested the existing putrefaction, I con- 

 cluded, that if the acid so diluted sufficed to destro\' the abounding putrefactive 

 organisms which must have been present among the textures in that case, it 

 must surely be trustworthy for compound fracture. We have accordingly 



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