230 ON RECENT IMPROVEMENTS IN THE 



tions by the acid (antiseptic suppuration) ^ is of course diminished ; and the less 

 the discharge, the less frequently is it needful to change the dressing. The 

 protective also keeps the surface of the sore moist, and so prevents the discharge 

 from being pent up and causing inflammatory disturbance from tension, as is 

 apt to be the case beneath the crust of inspissated pus in a dry dressing. The 

 lint is also kept from sticking to the sore and tearing off the newly formed 

 epidermis when it is removed. 



But it must always be remembered that the protective, in proportion to 

 the efficiency with which it discharges its function of preventing the irritation 

 of the acid, excludes also its antiseptic virtue, so that if putrefactive material 

 exists beneath it at any one point, the septic fermentation will spread over the 

 whole sore. Hence the necessity for having the boracic hnt to extend on all 

 sides beyond the oiled silk, for if the protective were to escape at any one place 

 from under cover of the antiseptic layer, it would necessarily conduct putre- 

 faction inwards beneath it. Hence also the importance of adopting thoroughly 

 efficient means of purifying the sore as a preliminary measure. 



But if those points are attended to, this mode of dressing will be found 

 to yield excellent results. The epithelial development, protected from needless 

 disturbance, proceeds at a rate altogether unknown under water dressing, and 

 cicatrization will often advance steadily in sores which, under ordinary treatment, 

 cannot be got to heal at all ; as when, through the unyielding character of 

 surrounding parts, the shrinking of a large granulating surface has put the 

 imperfect textures of the sore upon the stretch, and thus so reduced their vital 

 power as to make them liable to ulceration or sloughing under the influence of 

 stimuli which fail to arrest the healing of an ordinary vigorous sore, such as 

 solutions of astringent salts or the degree of putrefaction that occurs in water 

 dressing within twenty-four hours. This application also saves trouble to the 

 surgeon, for if properly used, it may be left unchanged for a period varying 

 from two to five days, according to the amount of the discharge. 



This last circumstance, together with the unirritating character of the 

 dressing, makes it peculiarly useful for skin-grafting. The manner in which 

 I have for a considerable time carried out Reverdin's beautiful principle is as 

 follows : The skin of the inner side of the upper arm having been lightly washed 

 with I to 20 watery solution of carbolic acid to purify its surface, a thin layer 

 of the integument is shaved off with a very sharp knife, so as to take barely 

 more than the epidermis, scarcely drawing blood or causing pain. The little 

 shaving is placed upon the thumb-nail of the left hand, moistened with a drop 

 of the boracic solution, and bits not bigger than pins' heads are successively 



^ See above, p. 149. 



