CONSTRUCTION AND CARE OF HOTBEDS 



the strips of wood on top of the walls, as is done 

 on wooden frames. 



Concrete makes a very substantial and com- 

 paratively cheap wall. These should be somewhat 

 thicker than the brick, and are laid up by the aid 

 of a square wooden frame or form the size of the 

 inside dimension of the pit, the excavation being 

 about eight inches larger all around. In laying the 

 wall, a rough concrete of sharp sand and gravel, 

 in the proportion of one part of cement to six or 

 seven parts of sand and gravel, is used. This is 

 placed in the space between the frame and wall 

 and tamped down firmly and until the moisture 

 rises to the surface; all four walls may be laid at 

 once to a height of one foot and then allowed to 

 harden before adding the succeeding foot; always 

 wet the last course of cement before adding fresh 

 concrete. After the wall is built up to the desired 

 height, a frame of narrow strips of wood should 

 be fitted to the top, as in the case of the brick wall. 

 Such a wall is very economical, warm, and durable. 



Having constructed the hotbed of the chosen 

 material, all that remains to do is to put it in com- 

 mission. To accomplish this, fresh horse manure 

 sufficient to fill the beds quite to the top will be re- 



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