222 Description of an improved Forcing Pit. 



of the back wall are holes with plugs, to let out the steam and 

 heat at discretion. 



The exterior of the wall supports the frame for the lights, 

 and is carried all round, about a foot above the height at 

 which the flue terminates, the flue being as much lower at the 

 front as the slope of the glass and mould make necessary. 



One half of the chamber is filled longitudinally with dung 

 at the commencement of forcing, and if the doors are kept 

 shut, this will afford sufficient heat from twelve to eighteen 

 days, according to the quality of the dung. As the heat de- 

 clines, the other half of the chamber is filled, and the tem- 

 perature is kept up by additions to the top of the dung, on 

 either or both sides, as it settles. When the united heat of 

 the two sides ceases to be sufficient, the side first filled must 

 be cleared out ; the old being mixed with some fresh dung, 

 must be replaced, and by thus successively adding and turn- 

 ing, the heat will be well kept up. As the season advances, 

 I have found the dung, which by that time has become short, 

 give sufficient warmth when mixed with leaves, and answer- 

 ing very well for melons through the summer. 



At the commencement of forcing with the pit, I fill half 

 of the chamber with dung before I lay in the bushes, leaves, 

 and mould, because this enables a labourer to tread the dung 

 well down, by standing on it as it is thrown in between the 

 iron bars, thus securing, at the first, a continuance of heat 

 for a considerable time. The bushes which I use to lay over 

 the iron bars are such as I obtain from the thinnings of the 

 plantations and prunings of shrubs ; they are laid across the 

 bars, and must be sufficiently strong to support the weight 

 of the mould above them. The leaves that are interposed 



