100 PATHOGENIC BACTERIA, 



of mercury, or, if this causes them to become too brittle, 

 in a watery solution of bichlorid. 



At present, in most hospitals, instruments are boiled 

 before using, and during the operation are either kept in 

 the boiled water or in carbolic solution. 



During the operation the wound is frequently to be 

 washed with carbolic solution or bichlorid of mercury, 

 i : 2000, applied by sterile sponges. To La Place belongs 

 the credit of observing that the efficacy of these germi- 

 cides is greatly increased by the addition of a small 

 amount of acid, by which their penetration is increased 

 and the formation of insoluble albuminates lessened. 



The knowledge that the action of germicides is chem- 

 ical, and that the destruction of the bacteria is due to the 

 combination of the germicide with the mycoprotein, is 

 apt to lessen our confidence in the permanence of their 

 action. Geppert has shown of bichlorid of mercury that 

 in the reaction between it and anthrax spores the vitality 

 of the latter seems lost, but that the precipitation of the 

 bichlorid from this combination by the action of ammo- 

 nium sulphid restores the vitality of the spore. 



Again, the fact that some of the antiseptics, as nitrate 

 of silver and bichlorid of mercury, are at once precipi- 

 tated by albumins, and thus lose their germicidal and 

 antiseptic powers, limits the scope of their employment. 

 I think it may be safely said that carbolic acid is the 

 most reliable and most generally useful of all the germi- 

 cides and antiseptics. 



The Disinfection of Sick-chambers, Dejecta, etc. 

 What has just been remarked concerning the unreliability 

 of many of the germicidal substances is eminently a 

 propos of the disinfection of dejecta. It is useless to 

 mix bichlorid of mercury with typhoid stools or tubercu- 

 lar sputum rich in albumin, and imagine these substances 

 rendered harmless in consequence. It should not be for- 

 gotten that the sick patient is less the means of convey- 

 ing the contagium than the objects with which he is in 

 contact, which can be carried to other rooms or houses 



