Application of Heat to Fruit Borders^ &;c. 55 



and the colouring and flavouring of the fruit, very much depend 

 upon the position of the roots, both as it regards heat and air, 

 as well as suitability of soil, there can be little doubt, for this 

 has been already well ascertained; therefore, I feel it superfluous 

 to enlarge upon the principles upon which a different practice is 

 based. Every day's experience, as well as occasional experiment, 

 must point out equally to the scientific and practical man, that 

 some change in the relative temperature necessarily existing in 

 such countries as these, between the roots and branches of trees 

 put into a state of premature excitement by forcing, is very 

 desirable. With this object in view, I propose heating the 

 border alluded to through the means of hot-water pipes, as will 

 at once be understood by referring to the plan and sections, 

 ^gs. 13. to 17., p. 50. to 54f. The chamber containing the pipes 

 is formed along the one end and front only of the vine border, 

 having small minor chambers or drains, 1 ft. square, crossing it 

 at regular distances, with open side walls which may be covered 

 over, either with short pieces of charred timber, long-shaped 

 bricks, or large slates ; the spaces between these minor air- 

 conducting chambers to be filled up with broken stones or 

 brickbats. The whole is to be covered over with a stratum of 

 limestone broken very small, and then by a firm thick sod with 

 the grass side down, over which the compost is to be laid, to the 

 depth of 2^ ft. next the house, and about 2 ft. at the walk or 

 chamber. Thus, whenever the branches of the vines are in- 

 troduced inside the house, the valves may be turned on the 

 outside pipes, and the requisite temperature obtained for the 

 roots. Calculating according to the ordinary principles of cir- 

 culation, I conceive that a regular current through the minor 

 chambers will be the result of heating the air in the pipe 

 chamber in front ; and also that the heat will find ready access 

 through the open side walls of the cross chambers, amongst the 

 stones or brickbats forming the bottom of the border between. 

 At the same time I purpose having a small plug-hole opening 

 opposite the end of each minor chamber, through the front 

 parapet, into the house ; so that at any time, if found requisite, the 

 heat derived from the outside chambers (which may be expected 

 to be very moderate) may be admitted into the body of the 

 house. Any necessity for this, however, is not at all likely, as 

 with the existing means of heating the house described, we find 

 we have an ample supply for all the purposes intended. This 

 application of heat to the roots may easily be regulated by 

 having a thermometer hung in a box in the border. I would 

 also suggest that a slight covering of rotten dung or leaves will 

 be requisite over the surface, for the purpose of retaining the 

 heat, as well as protecting the roots and stems that may be near 



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