Jan.] THE forcing garden. 509 



by Speedily and M'Phail long ago, and, until the present 

 time, their conjecture has been verified. We find, by a com- 

 munication in the Hort. Trans., that Mr. Gunter, at his gar- 

 dens at Earl's Court, tried steam as a substitute for tan, by 

 introducing it into a vacuity in the bottom of the beds. His 

 beds v/ere formed of , mould, and the plants planted out on 

 them, the whole being supported on rafters, covered in some 

 parts with brush-wood, and in others with perforated planks. 

 The heat obtained from the steam was found sufficient, but 

 what is rather singular, no vapour penetrated through the 

 mould, which soon became so dry and burnt up, that even 

 waterings repeated often were not sufficient to keep the mould 

 in the beds in a state fit for vegetation. In the gardens of 

 Count ZubofF, at Petersburg, stqam. has been applied to heat 

 a large cistern of water, the whole size of the pit, which, 

 when once heated, continued to give out its heat gradually and 

 for a long time. 



Steam-pipes have often been introduced into pits, and co- 

 vered with fragments of stone, gravel, saw-dust, and coal- 

 ashes, upofi ihe surface of which the plants in pots w^ere some- 

 times placed, and in other cases plunged into the latter mate- 

 rials ; and in some cases, the cavity in which the pipes were 

 placed was covered with perforated planks, for the ascent of 

 the heat; but, in most of those instances, the success was far 

 short of that of pines plunged in a bottom heat, produced 

 either from tan, leaves, or dung. The refuse in the process of 

 dressing flax has been used in many parts of Scodand, to pro- 

 duce a bottom heat, but the heat produced has been found too 

 violent, and of short duration. AJoss, (flT/pnt/m,) has been 

 suggested lately by Mr. Street; and, as its decomposition and 

 fermentation proceed slowly and never violent, it is proba- 

 ble that it may be successfully used as a substitute for tan, 

 leaves, &c. 



Having so far entered into detail on the means of obtaining 

 a sufficient degree of bottom heat, for the growth of these 

 plants, we will now proceed to detail their general manage- 

 ment throughout the year, in the three departments of nursing, 

 succession, and fruiting pits or beds ; and in so doing, we 



4d 



