52S 



THE PRACTICAL GARDENER. 



scnting an angle to tlic liorizon suited to tlic purpose for which 

 it is intended ; if for late forcing, or pine-stoves, an elevation 

 generally of thirty-five degi'ees will answer; hwt if for early 

 forcing, the elevation will require to be more upright, to admit 

 of the rays of the sun acting sufficiently powerful in the early 

 part of the season, when the sun is low in the horizon. 



ON HEATING IIOT-IIOUSES. 



Ilot-houscs arc generally heated by means of combustible 

 matters consumed in an oven or furnace, which is generally 

 placed behind the house, although sometimes placed in front, 

 or at the ends. The heated air, together with the smoke, is 

 made to pass into the house enclosed in a flue, which, for the 

 most part, stretches along the front part of the house, at some 

 little distance from the parapet wall. This distance is greater 

 or smaller, according to circumstances, but the flue should 

 always be placed as near the front as convenient, that being 

 the coldest part of the house. As the heat naturally ascends, 

 it is necessary that the first and greater heat should be allowed 

 to escape as near the lower part of the house as possible, an 1 

 if a sufficient heat be kept up here, it will readily heat the 

 higher parts. 



Steam, of late years, has been employed in heating hot- 

 houses, but the expense of getting up the apparatus, and of 

 keeping it in repair, has prevented it from being brought into 

 general use. Upon a small scale, it is not advisable, as the 

 expense is much greater than the more original method ot 

 heating by moans of brick-built flues. 



In 1792, Mr. Butler, then gardener to the Earl of Derby, 

 was amongst the first who tried the application of steam in 

 heating a cucumber-house, and it was the first successful at- 

 tempt in that improvement. The idea, however, was sug- 

 gested a few years previously by a person in Liverpool. Little 

 notice was taken of it till ISIG, when it was revived, and 

 has since been tried in many places ; in some it still con- 

 tinues to be used, and in others it has been abandoned, in con- 

 sequence of the expense. Fuel, in most parts of the kingdom, 

 is an expensive article, therefore the mode of heating hot- 



