20 



BULLETIN 527, U. S. DEPARTMENT OF AGRICULTURE. 



serve to strengthen the corner joints, and they are used as handles 

 when removing the sash from the frame. The sash when in use is 

 laid on the frame, the weight holding it in place. 



Figure 27 shows a simple one-sash cold frame that can be used also as 

 a hotbed by placing it over an excavation in which has been placed 2 

 inches of ashes or stone, 3 or 4 inches of straw, and a layer of fresh horse 

 manure. The thickness of the manure will vary from 6 to 24 inches, 



£/VD W£~l>1/ 



<s/&£ \//^yi/ 



Fig. 27.— Cold frame. 



depending on the climate and the season. Above the manure, 2 or 

 3 inches of straw and 5 or 6 inches of mellow soil are placed. When 

 the frame is used as a cold frame it is placed directly over the soil in 

 which the vegetables are to be grown ; this soil should be put into a 

 good state of tilth before the frame is built. 



The material required for the frame shown in figure 27 is one piece 

 of board f by 12 inches by 15 feet, one piece \ by 8 inches by 3 feet, 

 one piece 2 by 4 by 21 inches (if a piece of 2 by 4 inch dressed lum- 



