60 HORTICULTURAL MANUAL. 



areas are occupied by what are known as forcing pits, as 

 shown by. end section in Fig. 28, the hot-beds and cold- 

 frames are not dispensed with. But it is so cheap and 

 simple in construction that it is found at the homes of 

 amateurs across the continent and its use is on the increase. 

 After the first crop, when the bottom heat has lessened, it 



FIG. 28. End view of forcing pits heated by hot-water pipes. 



is useful for rooting cuttings of immature growth or those 

 of dormant woody growth. 



In making and filling the pit a few essentials must be 

 kept in mind : (a) At the North the pit should be dug in 

 the fall and filled with coarse manure to prevent freezing. 

 In digging make it large enough for the frame to set on 

 the filling so as to settle as the manure goes down. The 

 commercial hot-bed sash are three feet wide and six feet 

 long. For a bed with three sash the pit should be excavated 

 nine feet and six inches long, six feet six inches wide, and 

 thirty inches deep, for ordinary home use. 



(b) When the time arrives for starting the heat the filling 

 is taken out and about twenty inches of horse manure are put 

 in. This should be well fined and placed in layers evenly 

 so as to secure even settling when the frame is put on. If 

 the filling is quite dry it is best to wet the layers as placed 

 to give the needed moisture. 



If forest leaves are obtainable it is best to mix them with 

 the manure in filling, (c) The frame is made, as shown in 

 Fig. 29, with the back six to eight inches higher than the 

 front, to favor the reception of the sun's rays and to carry 



