296 Life and Health 



action, and these are called antiseptics. The word "disin- 

 fectant " is used with more or less confusion to cover both 

 these words. 



Disinfection is strictly the destruction of the germs of 

 disease by means of heat, chemical agents, fumigation, 

 or fresh air. An antiseptic, when used in a very strong 

 dose or for a long time may act as a germicide, while a 

 germicide in too weak solution to act as such may serve 

 only as an antiseptic. 



A deodorant is a substance that removes or conceals offen- 

 sive odors. Deodorizers are not necessarily disinfectants. 



462. Air and Water as Disinfectants. Nature has pro- 

 vided for our protection two most efficient means of dis- 

 infection, pure air and pure water. The air of crowded 

 rooms contains large quantities of bacteria, whereas in 

 pure air there are comparatively few, especially after rain, 

 which carries them to the earth. 



In water tainted with organic matter putrefactive bac- 

 teria will flourish, whereas pure water is fatal to their 

 existence. Surface water, because it comes from that 

 part of the soil where bacteria are most active, and where 

 there is most organic matter, generally contains great 

 quantities of these organisms. 



463. The more Common Disinfectants. Disinfection 

 must be secured by other means than fresh air and clean- 

 liness. The destruction of infected material by fire is, of 

 course, a sure but costly means of disinfection. Heat in 

 various forms, as dry heat, steam, and boiling water, is a 

 valuable disinfectant and does not injure most fabrics. 

 These agents are generally used in combination with vari- 

 ous chemical disinfectants. 



Certain chemical agents that are capable of destroying 

 micro-organisms have come, of late years, into general use. 



