HOT BEDS 21 



the flue in the hot bed. The flue should divide into two 

 lines and unite again at the farther end of the bed. Tile 

 is commonly employed in building the flue, although brick 

 may be used. 



31. Construction. Manure heated hot beds are con- 

 structed by digging a pit fifteen to thirty inches deep and 

 six feet wide and placing over it a frame as long as may 

 be desired. The front of the bed should be six inches lower 

 than the back so that the glass may have the proper slope 

 toward the sun. The common practice is to build the front 

 six inches high and the back of the bed twelve inches high. 

 Fig. 8, which is a cross-section view of a hot bed, shows 

 the general features of construction. The frame should be 

 strongly constructed of durable lumber, such as chestnut or 

 cypress planking, and 2X4 inch posts. Cross bars should 

 be placed from the front to the back of the bed at regular 

 intervals to stiffen the frame. 



The frame of the hot bed is constructed to support the 

 sash, which is commonly 3X6 feet, and glazed with 10X12 

 inch glass. Smaller glass is sometimes used, but three 

 sections of 10X12 inch glass is preferred by most growers. 

 Sash is often made and used in sizes larger than 3x6 feet, 

 but larger sash is much heavier and more awkward to 

 handle, also a bed over six feet wide cannot be worked 

 advantageously. The sash should be made of cypress or 

 cedar to assure durability. 



The depth of the pit is determined by such factors as 

 the time of year, whether the weather is severe or mild, 

 and the kind of crop to be grown. Such crops as radishes 

 or lettuce do not require so much heat as do tomatoes or 

 peppers. 



32. Preparation of the Manure. Horse or mule manure 

 may be used as a source of heat. The manure should be 



