VIL 
ANTISEPTICS AND DISINFECTANTS. 
GENERAL ACCOUNT OF THE ACTION OF. 
THE term autiseptic is used by some authors to designate an 
agent which destroys the vitality of the microérganisms which pro- 
duce septic decomposition, and others of the same class. We prefer 
to restrict the use of the term to those agents which restrain the de- 
velopment of such microédrganisms without destroying their vitality. 
The complete destruction of vitality is effected by germzcides or dis- 
infectants. Material containing the germs of infectious diseases: is 
infectious material, and we disinfect -it by the use of agents which 
destroy the living disease germs or pathogenic bacteria which give 
it its infecting power. Such an agent is a disinfectant. But we ex- 
tend the use of this term to germicides in general—that is, to those 
agents which kill non-pathogenic bacteria as well as to those which 
destroy disease germs. All disinfectants are also antiseptics, for 
agents which destroy the vitality of the bacteria of putrefaction ar- 
rest the putrefactive process ; and these agents, in less amount than 
is required to completely destroy vitality, arrest growth and thus 
act as antiseptics. But all antiseptics are not germicides. Thus a 
concentrated solution of salt or of sugar will prevent the putrefac- 
tive decomposition of organic material, animal or vegetable ; but these 
agents do not destroy the vitality of the germs of putrefaction. In 
a certain degree of concentration they are antiseptics and are largely 
used for the preservation of meats and vegetables. In the same way 
many mineral salts in solutions of various strengths act as antisep- 
tics, and some of these in still stronger solutions are disinfectants. 
Thus mercuric chloride, when introduced into a culture solution in 
the proportion of 1: 300,000, will restrain the development of anthrax 
spores, but to insure the destruction of these spores a solution of 
1 :1,000 must be used. As arule, the difference between restraining 
action—antiseptic—and germicidal power—disinfectant—is not so 
great as this. We give below some recent determinations by Boer 
which illustrate this point, the test organism being the bacillus of 
typhoid fever in a culture in bouillon twenty-four hours old : 
