247 



iained may, through the action of these organisms, be lost. The practi- 

 cal lesson taught here is to apply nitrogenous foods in a moderate man- 

 ner and avoid every unnecessary excess. 



PATHOGENIC FERMENTS. 



There are also other forms of ferments in the soil of an objectionable: 

 nature which are not related to the nitrifying organism. It has been, 

 observed in France that in localities where animals are interred which 

 have died of charbon the germs of this infectious malady persist in the 

 soil for many years, and that, especially when cereal crops are cultivated 

 upon such soil, there is great danger of contaminating healthy cattle 

 with the same disease. In one case it was observed that many sheep 

 which were pastured in a field in which, two years before, a single 

 animal which had died of charbon was buried, were infected with the 

 disease and died. In like manner, it is entirely probable that the germs 

 of hog cholera may be preserved in the soil for many years to finally 

 again be brought into an activity which may prove most disastrous for 

 the owners of swine. Every effort should be made by agronomists to 

 avoid infecting the soil by the carcases which are dead from any 

 zymotic disease. Cremation is the only safe method of disposing of 

 such infected carcases. The investigations of scientists have shown 

 that there are many diseases of an infectious nature due to these germs, 

 and that these germs may preserve their vitality in the soil. Among 

 others may be mentioned yellow fever and tetanus. 



USE OF SEWAGE AS FERTILISER. 



For the reason given above, the agronomist who also has at heart 

 the health and welfare of man and beast can hardly look with favour 

 upon any of the plans which have been proposed for the use of sewage 

 from large cities for irrigation purposes. There is scarcely a time in 

 any large city when some infectious disease, due to the activity of 

 germs, does not exist, and the sewage is liable at all times to be con- 

 taminated therewith. In view of the fact that the vitality of the 

 germs mentioned above may be continued for a long time in the soil, 

 it is fair to conclude that it is of the utmost importance to avoid the 

 contaminaton of the soil, where it is to be uesd for agricultural pur- 

 poses, with any of the dejecta whch may come from those infected 

 with any zymotic disease whatever. 



(To be continued.) 



