16 NATURE TEACHING. 



in diameter, should be bored in the bottom 

 of each box in order to secure free] drainage. 

 In addition to wooden boxes useful seed boxes 

 may be made from the bottoms of kerosine 

 tins. 



2. The soil for filling the boxes should 

 be prepared by sifting, first, through a sieve 

 having holes of about an inch in diameter ; 

 this will remove the large stones : the sifted 

 soil should next be passed through a second 

 sieve having holes of about a quarter of an inch 

 in diameter ; this will separate the gravel from 

 the fine soil. A small quantity of soil should 

 be passed through a still finer sieve. It is 

 advisable to prepare a good supply of soil and 

 to store it in a dry place, so that, whenever 

 required, stones, gravel or fine soil may be 

 available. 



3. A tool for levelling the soil, as it is 

 placed in the boxes, is wanted. This is simply 

 supplied by a piece of smooth board, half an 

 inch in thickness and about 8 by 4 inches in 

 area, with a suitable knob or handle fixed on 

 the back. 



4. A supply of dry, finely chopped grass, 

 such as is obtained by mowing lawns, or pre- 

 ferably of cocoa-nut fibre refuse, is required. 



