12 MICROBES AND THE MICROBE- KILLER. 



The New York State Board of Health on one occasion 

 recommended sulphurous- acid gas— the fumes of burn- 

 ing sulphur — as a preventive and disinfectant for diph- 

 theria. But the special germ, the streptococcus diph- 

 therialis, is not destroyed by that gas. It yields to three 

 agents only — carbolic acid, corrosive sublimate, and my 

 microbe killer, and the first two of these are powerful 

 poisons and as dangerous to the patient as they are to 

 the microbe. 



It is worthy of mention here that diphtheria is not 

 confined to members of the human family. Animals 

 are liable to it, and a case is mentioned where a kitten 

 conveyed the disease- to four members of one family be- 

 fore the truth Became known and the animal could be 

 killed. The symptoms in that instance were unusually 

 virulent, but no deaths ensued. 



Most of the microbes or bacteria that are to be found 

 in the atmosphere come from the ground, or from the 

 breath, or sputa, or persons of individuals. Heavy 

 rains tend to wash them out of the air, but, when thus 

 thrown to the soil, the moisture favors their increase, 

 and thus, as the ground dries, they may be carried back 

 into the atmosphere in increased numbers. 



It is an error, however, to suppose that the atmosphere 

 is the principal nidus of the disease forms. Bacteria, 

 -microbes, and micro-organisms of all kinds exist in in- 

 finite numbers in the soil. Some observers consider 

 that to be their chief breeding place. All are not dis- 

 ease-producers, but all seem to exercise some function, 

 and the most plausible suggestion yet made upon this is 

 that, by inducing a process of fermentation in the soil, 

 they bring about chemical decompositions which liberate 

 elements that are necessary to the nutrition and devel- 

 opment of higher forms of life. 



Among disease germs that are found in the soil, those 

 of typhoid fever (see Plate XI., Nos. 43 and 44), malaria, 

 and tetanus (see Plate XXII., No. 85) are most frequent, 

 and hence it is that the breaking up of new land, 

 especially in damp places, so frequently produces ague 



