BACTERIA IN NATURAL PROCESSES. 123 



Thus the farmer's life from year's end to year's 

 end is in most intimate association with bacteria. 

 Upon them he depends to insure the continued 

 fertility of his soil and the constant continued 

 production of good crops. Upon them he de- 

 pends to turn into plant food all the organic ref- 

 use from his house or from his barn. Upon 

 them he depends to replenish his stock of nitrogen. 

 It is these organisms which furnish his dairy with 

 its butter flavours and with the taste of its cheese. 

 But, on the other hand, against them he must be 

 constantly alert. All his food products must be 

 protected from their ravages. A successful farm- 

 er's life, then, largely resolves itself into a skilful 

 management of bacterial activity. To aid them 

 in destroying or decomposing everything which he 

 does not desire to preserve, and to prevent their 

 destroying the organic material which he wishes to 

 keep for future use, is the object of a considerable 

 portion of farm labour ; and the most successful 

 farmer to-day, and we believe the most successful 

 farmer of the future, is the one who most intelli- 

 gently and skilfully manipulates these gigantic 

 forces furnished him by the growth of his micro- 

 scopical allies. 



RELATION OF BACTERIA TO COAL. 



Another one of Nature's processes in which 

 bacteria have played an important part is in the 

 formation of coal. It is unnecessary to emphasize 

 the importance of coal in modern civilization. 

 Aside from its use as fuel, upon which civilization 

 is dependent, coal is a source of an endless variety 

 of valuable products. It is the source of our 

 illuminating gas, and ammonia is one of the prod- 



