2B6 Centre Bed in a Hot-hmise 



of great depth ; instead of occupying high sites, occupies the 

 lowest ; instead of being well drained, is usually saturated 

 with water to the very roots of the herbage it bears ; instead 

 of a draining stony subsoil, stones are almost totally absent 

 from it, and the subsoil is a water-holding clay. Although, 

 like heath-mould, the surface soil exhibits spongy masses of 

 fibres, it lacks the sand which prevails in heath-mould; 

 and, when wet, is not friable, but oozy and soapy. Heath- 

 mould, by means of its dry nature, its vegetable fibre, and 

 its sand, is disposed to continue light, open, and porous : peat, 

 from its muddy adhesive nature, the great rapidity with which 

 vegetable fibre decays in it, its lack of sand, or from other 

 causes, speedily subsides into a dense, inert, coagulate mass. 

 While heath-mould is most important to the gardener, peat 

 is not only totally unfit for, but even inimical to, most of the 

 purposes of floriculture ; although, as nothing in nature is 

 left unused, it is the very soil in which willows, many grasses, 

 the rushes, the sedges, and similar families, thrive and 

 luxuriate. 



If my brother gardeners admit the distinction I have 

 striven to show, I hope they will adopt it. 



I am, Sir, &c. 

 Feb. 16. 1831. J. D. 



Art. X. An Account of the Application of hot Water to heating 

 the centre Bed in a Hot-house, in lieu of Tan. By J. T. Alcock, 

 Esq., of Mount Hill, Caermarthenshire. 



Sir, 



According to your desire, I send you a more detailed 

 account of the application of hot water to heating the central 

 bed in a hot-house, in lieu of tan, or any other fermenting 

 matter. 



From the reservoir {Jig. 51. a) I branched a small deliver- 

 ing pipe (6) 1 f in. in diameter, which was continued to the 

 opposite angle of the bed, where it formed a dip of 10 in. at 

 c, and returned to the reservoir at d. I then constructed 

 laterals of | in. leaden pipe {e\ which were soldered into 

 the delivering branch at 8 in. apart, and, having crossed the 

 bed, dipped into the returning branch as at c. The space un- 

 derneath was previously filled up with small stones and gravel, 

 with about 2 in. of sand on the surface, on which the pipes 

 were placed. The whole was then covered with sand, about 

 4 in. deep, and it worked admirably. 



