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to microscopic organisms, including fungi ; shall bacteria 

 then, a family of fungi, be exceptions to the general 

 rule ? As to anthrax, the case is answered ; the disease is 

 endemic in certain districts, that is, the bacilli grow out- 

 side of the animal body only in these districts. Koch has 

 recently endeavored to elucidate the reasons for this. 

 He ascertained that the growth of the anthrax bacilli re- 

 quires moisture and a temperature of 15 C. It is evi- 

 dent, therefore, why anthrax is not endemic in districts 

 whose surface temperature fails to reach this point. 

 Koch further ascertained, from the official reports of 

 Prussian veterinary surgeons, that after the overflow 

 of rivers and lakes an outbreak of anthrax had been 

 frequently observed in cattle pasturing at certain points 

 along the banks. He found by experiment that the 

 bacilli flourish in infusions of various grasses, grains, 

 and vegetables. Hay infusion is usually a poor soil, be- 

 cause of acid reaction ; when rendered neutral or slightly 

 alkaline, the bacilli grow in it luxuriantly ; but it had 

 been long before stated by German and French observ- 

 ers that the anthrax districts usually had a calcareous 

 soil. Hence he conjectures that in such districts the 

 alkalinity due to the lime may render even hay a soil 

 favorable to the anthrax parasite ; that it may usually 

 grow on decaying plants in such districts. That anthrax 

 is especially prevalent in autumn seems to result in part 

 at least from the fact that these bacilli, like many other 

 fungi, grow only on dead plants. It might be interesting 

 to review for comparison with anthrax the facts which 

 establish the association of various infectious diseases 

 cholera, yellow fever, the malarial fevers, for example 

 with local influences of soil and temperature ; the ori- 

 gin of typhoid fever in particular wells and springs, as 

 has been conclusively established by observations upon 

 the German and Austrian soldiery. Yet such discussion 

 would transcend my time and my province, since I have 

 attempted to portray what has been, not what remains 

 to be accomplished. 



Certain popular arguments against the morbid agency 



