262 DESCRIPTION OF A MELON AND PINE PIT. 



conveniently contain, I have applied the structure erected for pine-apple 

 plants to the culture of melons only, during the summer. 



These having succeeded most admirably, and a great number of 

 gardeners having examined my machinery, and given their unqualified 

 approbation of it, I send the following description of it to the Horticul- 

 tural Society, flattering myself that it will be found, in the aggregate, 

 superior to any now employed, which can be erected at so small an 

 expense, and managed with so little cost and trouble. It consists of a 

 hollow wall, similar in every respect, as to construction, to that described 

 by Mr. Silverlock in the Transactions of the Society*; and I cannot 

 describe it better than by using his words : " It is built nine inches thick, 

 with sound even-sized bricks, placed edgeways, the joints being carefully 

 made, and laid with the very best mortar. The bricks are placed with 

 their faces and ends alternately to the outside, so that those which have 

 their ends exposed become ties to the surfaces of the wall. In each 

 succeeding course, as the wall is built, the bricks with their ends out- 

 wards are placed on the centre of the bricks which are laid lengthways 

 in the course below. Thus a hollow space is formed in the middle of the 

 wall, of four inches in width, which is only interrupted where the tying 

 bricks cross it, but there is a free passage for air from top to bottom of 

 the wall." 



My front wall is four feet, and my back wall five feet six inches high, 

 enclosing a space of six feet wide and fifteen feet long, and the walls are 

 covered with a wall-plate, and with sliding lights, as in ordinary hot- 

 beds. 



The space included may be filled to a proper depth with leaves, or 

 tan, when it is wished to promote the rapid growth of plants ; but at 

 present it contains only nine large pots, in which the melon plants grow, 

 and the stems of these are supported by a trellis at a proper distance 

 from the glass. The wall is externally surrounded by a hot-bed com- 

 posed of leaves and horse-dung, by which it is kept warm; and the warm 

 air contained in its cavity is permitted to pass into the inclosed space 

 through many small perforations in the bricks. At each of the lower 

 corners is a passage, which extends along the surface of the ground, 

 under the fermenting material, and communicates with the cavity of the 

 wall, into which it admits the external air to occupy the place of that 

 which has become warm and passed into the pit. The entrances into 

 these passages are furnished with grates, to prevent the ingress of vermin 

 of every kind. The hot-bed is moved and renewed in small successive 



* See Horticultural Transactions, vol. IV. page 224. 



