are kept. He depends upon it not only to enrich his 

 soil, but also to heat it by the process of fermenta- 

 tion. More and more in Paris, however, the horse 

 is being replaced by the motor-car, and therefore 



FIG. 47. A Field of Maize in Eastern Kansas. 



horse-manure is becoming dearer. Here is another 

 difficulty in the way of the gardener. 



On the whole it seems likely that his work will 

 get more difficult as time goes on, and that his 

 methods will perhaps have to be changed with 

 changing times. From what we know of the 



