182 IMPROVEMENTS IN THE CULTURE OF 



a good stock of roots before he renders it an inde- 

 pendent plant. 



Where heat is to be supplied from fermenting horse- 

 dung, we should recommend for trial a pit invented 

 by J. West, of Castle Ashby, in Northamptonshire. 

 (fig' 22.) Nine years' experience enable its in- 

 ventor to recommend it for neatness of appearance, 

 the power of regulating the heat to the greatest 

 nicety, and for forcing asparagus, strawberries, and 

 the most delicate kinds of cucumbers. By raising 

 the walls of the pit higher above the earth, it is 

 evident it would answer equally well for growing 

 Pines, or forcing shrubs or tall growing plants. 



The dung is placed in a chamber (E) three feet 

 and a half deep, being about eighteen inches below 

 the surface-line ; the walls (G) which surround 

 it are nine-inch brick- work ; both on the front and 

 at the back of the chamber are two openings (A), 

 about to feet six inches square each, with move- 

 able doors, through which the dung is introduced ; 

 the doors fit at bottom into grooves (B), and are 

 fastened by a wooden pin and staple at top. In 

 front of the doors, is a small area (c) sunk in the 

 ground, surrounded by a curb of wood, by which 

 the introduction or removal of the dung is facili- 

 tated. Along the centre of the chamber is a bar 

 (D), which serves as a guide for packing the dung ; 

 and across the top, at intervals of twelve inches, 

 are placed, on their edges, cast-iron bars (H), two 

 inches wide, and three quarters of an inch thick, 

 to support a layer of small wood, bushes and leaves 

 (i), over which is laid the soil for the plants (K). 



