23£ VARIOUS METHODS OF HEATING DESCRIBED IN DETAIL. 



menl beside, the most abundant crops are obtained. Mr. Rob- 

 erts, of Raby Castle, author of a treatise on vine culture under 

 glass, and a good authority on the subject, says : — " Fault has 

 been found with me for recommending heat to the roots of vines 

 by fermenting manure, on account of its unsightliness ; but 

 practice convinces me that without a corresponding degree of 

 temperature betwixt the root and top, you cannot produce good 

 grapes. I intend, however, to do away with the unsightliness 

 of manure, in my new vine borders, by heating them on another 

 plan." Such is the testimony of men who stand first in their 

 profession, — men of undoubted probity and extensive expe- 

 rience, and who, as authorities on these matters, may be fully 

 relied on. No one, who once has seen the extensive gardens 

 which they superintend, will dispute the propriety of the practice 

 of placing fermenting manure on the surface of a vine border. 

 But I must differ in my opinion from Mr. Roberts in regard to 

 its eflfects. It may not be positively injurious, but Mr. Roberts 

 has failed to prove that it is positively beneficial. Moreover, if 

 he has succeeded in imparting a temperature to his vine border 

 equal to the atmosphero at which he keeps his vinery, he must 

 have a body of manure equal in bulk to the vinery itself. Heat 

 travels with extreme slowness through the damp, confined air 

 of dung-beds, and the tMfficulty of getting heat to travel down- 

 wards is well known. A body of fermenting material may 

 communicate its heat to the mere surface of the soil on which 

 it lies ; but the moisture it absorbs from the atmosphere, as well 

 as its saturation by rains, is connnunicated to the soil in place 

 of heat, so that in reality the good produced is nearly, if not 

 altogether, counterbalanced by the evil. The plan Mr. R. 

 intended to adopt has i.ot, as far as I know, been made public ; 

 but probably it was some kind of chambered border, with arti- 

 ficial heat radiating beneath it. 



The annexed drawing represents a chambered border, heated 

 with a hot-water tank, which is supplied with water from the 

 pipes when it can be spared from the atmosphere of the house, 

 by a tap fixed on the pipe, as shown at a, in the end section. 

 If the water is allowed to flow into the tank from the boiler for 

 the space of an hour, a sufficiency of heat will be communicated 



