SILVER NITRATE 49 



destruction of any products of bacteria capable of 

 producing disease. 



A chemical is tested for its antibacterial properties 

 in several ways, chief among which is the immersion 

 of some of the pure bacterial growth in solutions of 

 various strengths of the chemicals. 



Some of the individual disinfectants are: 



Bichloride of Mercury (corrosive sublimate). This is 

 soluble in 16 parts of cold water. One part in 100,000 

 inhibits most bacteria. In twice that strength many 

 kinds are killed in a few minutes. Spores are destroyed 

 in 1 to 500 solution in water within one hour. In order 

 to obtain the best results with this corrosive sublimate 

 it is necessary to have an acid reaction, so that most of 

 the tablets now on the market are made up with an 

 acid having no effect upon the mercury salt. This is 

 particularly true when the material to be disinfected 

 is pus, blood, feces, or the like. It is wise to use a 

 strength of 1 to 500 for one-half an hour when any 

 such organic material is present. The disadvantages 

 of this substance are, beside that mentioned above, 

 that it corrodes metals, and is rather hard on the skin. 

 It is well to add some coloring matter to the solution 

 for the purpose of identification, since this is a rapidly 

 acting, corrosive, deadly poison. Great care should be 

 used in keeping the tablets and solutions, as many 

 accidents have occurred. Being odorless it attracts 

 no attention. 



Silver Nitrate. Park says that this salt has one- 

 fourth the value of the preceding as a disinfectant, 

 but nearly the same value in restraining bacterial 

 growth. 

 4 



