i84 THE ADDRESS IN SURGERY DELIVERED BEFORE 



in solution of carbolic acid. For, as india-rubber happily absorbs carbolic acid, 

 the drainage-tube is antiseptic when introduced. 



There is yet one other point to which I must allude, which is, that carbolic 

 acid interferes with the cicatrization of a wound, if it act directly on it. This 

 agent operates with special energy on the epidermis. Sometimes this is a 

 convenience. For example, if we dip the forefinger into a carbolic-acid lotion, 

 and hold it there for a second or two, we may be certain that the epidermis is 

 so imbued with the carbolic acid, that it is for the time antiseptic, and therefore 

 may be introduced into the cavity of an abscess or any other part which we 

 wish to explore ; and very valuable an antiseptic forefinger often is in that 

 way. But this action of the acid on the epidermis makes it interfere with 

 cicatrization ; and even the gauze, though generally perfectly free from irritating 

 influence upon the sound skin or an old scar, will frequently, if applied directly 

 to a wound, entirely arrest new epidermic formation, and sometimes excoriate 

 a tender young cicatrix. Something, therefore, must be interposed to protect 

 the wound from this effect of the antiseptic. What we have generally used 

 hitherto for this purpose is what we have called the ' oiled-silk protective ', 

 consisting of oiled silk varnished with copal varnish, which makes it much 

 less permeable to the carbolic acid. But, unfortunately, this is not a perfect 

 protective. It acts admirably until it becomes moistened ; but afterwards 

 the water that penetrates the substance conveys the carbolic acid in. I have 

 striven in various ways to get something perfect in that way ; and I have 

 lately been engaged in a manner which, though not yet completely successful, 

 may be mentioned on account of its interest otherwise. Some time since, 

 I tried the effect of an oil-paint on oiled silk, in the hope that the particles of 

 pigment, closely packed, might serve considerably to intercept the carbolic 

 acid, though the oily material that cements the particles is permeable to it. 

 The result was such as I had hoped, except that the material proved too stiff 

 for convenient use. A few weeks since, however, I happened to be going through 

 an india-rubber factory, and there I saw, among other things, the process of 

 mixing various pigments with caoutchouc ; and it occurred to me, might not 

 india-rubber, blended with some pigment, answer as a protective ? The india- 

 rubber is permeable to the carbolic acid ; but with the pigment it might not 

 be so. I first tried a coloured rubber that had been vulcanized, and then came 

 out a most curious and interesting circumstance. The sulphur in the vulcanized 

 india-rubber acting chemically on the discharge, the result was a stench like 

 rotten eggs, presenting an excellent example of decomposition without putre- 

 faction ; for there was no putrefactive fermentation — no spread of the decom- 

 position into the interior of the wound or abscess. It was limited to the exterior, 



