140 DESCRIPTION QF HOTHOUSES. 



back, and three or four in front, with both 

 ends corresponding with the back, and front 

 walls; having a frame- work of wood along the 

 top of the walls for the lights to fit closely upon, 

 with rafters fixed from back to front of the 

 pit, the same distance apart as the width of the 

 glass light, for the latter to rest and slide upon, 

 and which are generally from three to four feet 

 wide, the light well glazed and thoroughly water- 

 tight ; the pit should not be sunk much, and if 

 the bottom is naturally wet, it ought not to be 

 sunk at all, but the walls raised the height 

 before mentioned above the surface ; in this 

 method of growing pines, I must strongly 

 recommend hot water or steam heating in 

 preference to fire heat, the first for choice, 

 although I have seen the most brilliant success 

 attend the steam. The pipes may be carried 

 all round the pit, if there be sufficient space 

 between the bark in front, and the glass, if 

 not, have the pipes behind only, always allow- 

 ing a proper space below, for the bark bed, 

 which should be about three feet or three feet 

 and-a-half deep. 



