THE SOIL 119 



collected and placed on this heap, and, at intervals, a 

 layer of soil should be thrown over it to promote decay 

 and prevent unpleasant smells. The heap should be 

 kept damp throughout. Care should be taken to select 

 the place for the compost heap where it will not be 

 unsightly, and, if a low hedge is planted round the spot, 

 it need not disfigure the neatest garden. It is convenient 

 to have two heaps one in process of formation, the 

 other ready for use. 



To illustrate the influence of vegetable matter on 

 soil fertility, select in the school garden two beds, of 

 equal size, with similar soil, and conveniently near 

 together for purposes of comparison. Give one a good 

 dressing of stable-manure (which is vegetable matter in 

 a partially-decomposed condition), or a dressing from 

 the compost heap, or of such material as grass-cuttings 

 from a lawn or indeed of any available form of vegetable 

 matter. (There is a great difference in the rates of 

 rotting of various substances, some change so slowly as 

 to be troublesome in a garden ; stable-manure, owing to 

 its being already partly decomposed, is the most effec- 

 tive, rotting and mingling with the soil rapidly.) Give 

 the second plot no manure. Plant similar crops, at the 

 same time, on the two beds; the nature of the crop 

 adopted depending on time and local circumstances. 

 Keep a record of the character and growth of the crops, 

 noting the development and appearance of the plants, 

 the effect of dry weather or other climatic conditions. 

 Note the weight of the various parts yielded by each 

 crop, and, from time to time, observe the character of 

 the soil of each plot. These beds should be permanently 



