G02 THE PRACTICAL GARDENEU. [Ja?I, 



added the early and late forcing-pits, invented and much 

 used hy W. Atkinson, Esq., and which are intended for general 

 purposes, either for growing young pines, melons, cucum- 

 bers, or forcing flowers, strawberries, &c. The latter will 

 require no farther description than that of the engraving, which 

 is in itself sufficiently clear, but the former differing in a 

 material point, will require a little explanation. 



The danger often attending the admission of rank steam 

 into forcing-pits led to the invention of the accompanying one, 

 and it has been found in practice to answer every expectation. 

 This pit is sunk under the gi'ound-level, as shown both in the 

 section and elevation, and is heated by linings applied in the 

 usual way round the sides and ends. The heated air enters 

 through the back-wall between the open courses of brick-work, 

 but the steam is prevented from entering, at the same time, 

 farther than the cavity (C, See Plate), which is formed by 

 placing large slates parallel with the walls, and a few inches 

 from them. The heat from the front lining enters the front 

 wall, which is composed of brick pillars, the spaces between 

 them being filled with a large slate, through which sufficient 

 heat penetrates, while the rank and noxious steam is kept out. 

 This heat is intended to warm the atmosphere of the pit, and 

 finds its way into it through the cavity (c/), which is left open 

 at top. In the process of filling the body of the pit, some- 

 times mould, or other matter, may fall into the open cavity (d), 

 but this is easily got out by introducing a narrow hoe at the 

 ends, where a provision is made for that purpose, by taking 

 out the moveable stone or tile at (B). The advantage of this 

 pit is manifest: like those of M'Phail, rank dung may be 

 safely used, but it has this important advantage over such pits, 

 that a much less quantity of dung is required to heat them. 

 We have seen this pit in operation, and nothing could answer 

 the purpose better for which it was intended. Like the pine- 

 pits recommended by Mr. Aiton, this pit also is furnished with 

 a gutter in front at (E), for preventing the water falling into 

 the front linings, and which, without such a provision, would 

 chill the heat in them, and in continued wet weather render it 

 almost impossible to keep up the required temperature. 



