VARIOUS METHODS OF HEATING DESCRIBED IN DETAIL. 



245 



this appears to be substantially proved, by the invariable success 

 that has attended the culture of foreign grapes in cold houses, as 

 well as other facts suggested by experience, in the culture of 

 that noble fruit. The value and importance of the grape-vine 

 have already induced me to dwell longer on this subject, in con- 

 nection with heating, than I intended ; I therefore consider it 

 foreign to my subject to enlarge further on its culture, although 

 there is great room for speculation, theory, experiment, and 

 practical improvement. Indeed, it would be difficult for the 

 practical horticulturist to take hold of a subject affording a wider 

 field for successful experiment, and holding out brighter hopes 

 of beneficial results. 



Before concluding this chapter on heating, I will briefly notice 

 another system, more, however, on account of its novelty, than 

 applicability to the warming of hot-houses, although it has, in 

 some instances, been applied to this purpose. I refer to the 

 method of heating, by which the hot air is carried along by the 

 power of a steam-engine. This system is applied to the warm- 

 ing of large factories in England, and has been also applied, with 

 apparent success, in some large nursery gardens, in Germany. 

 The following description is from the pen of Mr. Marnock, the 

 able editor of the " Gardener's Journal," (Eng.,) and drawn from 

 his own observations of the apparatus, while visiting the gardens 

 of Baron Hugel, near Schonbrunn, where the system was in 

 operation at the time. 



" The most remarkable feature about this garden is the mode 

 of heating, which we shall now attempt to describe. In the 

 first place, there is a large fire-place constructed ; through this 

 fire-place two or more pipes are introduced ; the pipes are of cast- 

 iron ; one end of these pipes communicates with the common 

 atmosphere, the opposite end being introduced into a large box, 

 or flue ; in this flue is placed a fan, driven by a steam-engine, 

 which fan is made to revolve in this air-flue, at a short distance 

 from the fire-place. It will readily be understood, that, when 

 the fire is in action, with those iron pipes passing through it, 

 and terminating in the large air-flue, the revolving action of 

 the fan, in a direction to draw the common atmospheric air 

 through the iron pipes in the fire-place, will also force the heated 



