XIV 



Obituary Notices of Felloivs deceased. 



In the case of the mercurial dressings it became necessary to disinfect them 

 before use, because, the mercurial salts being non-volatile, bacteria falling on 

 them were not destroyed ; this was at first done by wetting them with 1/60 

 carbolic lotion, and later by heat. The greatest simplification was the 

 abolition of the carbolic spray. As bacteriological science advanced it was 

 shown that the bacteria floating in the air were rarely pathogenic, and, 

 indeed, were unable to grow in wounds and therefore might be disregarded. 

 Further they were present in the air in the spore form, and the carbolic 

 spray was shown to be ineffective in killing spores. When these facts were 

 demonstrated it became evident that the spray was unnecessary and did not 

 fulfil its object, and Lister accordingly gave up its use. No one was more 

 pleased than Lister to get rid of the spray ; so long as it was possibly of use 

 he did not dare to discard it, but once it was shown not to be necessary he 

 gladly gave it up. 



Lister had always a strong belief in the vis medicatrix naturae, and was 

 always pointing out facts which indicated how the tissues, if in a healthy 

 state, could to a certain extent prevent the growth of bacteria, and actually 

 destroy them. Indeed, he was the first to furnish definite proof that what 

 he termed the " vital action " of the tissues was a very potent agent in 

 protecting the body from bacterial invasion. He showed by experiments 

 with urine and milk how organisms cannot spread up canals lined with 

 healthy mucous membrane. He disinfected the orifice of the urethra and 

 the glans penis, and passed urine into a sterilised flask, which was then 

 plugged with cotton wool. This remained sterile for years, and one flask is 

 still in existence. A similar experiment was performed with milk ; the 

 udder and teats of the cow were disinfected and milk drawn into sterilised 

 vessels. This is a much more difficult test, as the air of cowsheds is full 

 of bacteria of all kinds, but several tubes of milk procured in this way 

 remained sterile, showing that bacteria were unable to penetrate up healthy 

 milk ducts. 



By the time that Lister gave up work he had simplified and perfected the 

 treatment of wounds to a very great extent. Antiseptics were no longer 

 brought in contact with wounds in any appreciable quantity, and the anti- 

 septics which might possibly get in were much less irritating than those 

 formerly employed. As a result there was much less discharge from the 

 wounds, and drainage was no longer necessary unless in exceptional cases. 

 Consequently, dressings might be left on for days, and when removed the 

 wound was found to be healed, while if easily absorbable catgut stitches 

 were employed, they came away of themselves. In fact, his ideal of 

 converting an open wound into a subcutaneous one had been practically 

 attained. Since that time further changes of a minor character have been 

 made which have added to the security of the aseptic result, such as the use 

 of boiling for disinfecting instruments and other materials, the sterilisation 

 of dressings, gowns and so on, in high-pressure sterilisers, the use of sterilised 

 rubber gloves, masks, etc. Other changes have also been made which, 



