226 



CASSELL'S POPULAR GARDEXING. 



that either mealy bug or scale thrives on Piaes on a 

 dung-bed. 



Melon and Cucumber Pits. — These have 

 been made of every possible form and size. Con- 

 structors at one time almost ran wild over Melon- 

 pits. Machinery was even erected to lift up the 

 growing beds by block and tackle, as the materials 

 of which they were composed lost bulk through their 

 decomposition. No amount of mechanical ingenuity 

 was spared to arrest the siuking away of the plants 

 from the light. Most of the old pits were far too 

 deej) to start with. As a crop of Melons may easily 

 be finished within four or five months from the time 

 of sowing, and as, moreover, they can only be grown 

 to any good purpose in the early spring, summer, and 

 autumnal months, it follows that Melon-pits need 



round. They reach to the base of the pit and up to 

 the ground-level, often beyond it. The linings are 

 also not seldom six inches or even a foot narrower 

 at bottom. The off-side of the lining is finished 

 with four-and-half or nine-inch brickwork, accord- 

 ing as the soil is difficult or easy to keep out of the 

 lining. Our illustrations of Melon-pits with linings 

 will assist in the understanding of the text. It 

 is obvious at a glance that this blank space may 

 readily be filled in with litter or with hot manure, 

 and in either case it would aft'ord a lining to its 

 outer walls so far as it surrounded them, cold- 

 proof in the one case, and an active source of heat 

 where manm-e, leaves, or dung were used. The 

 parts of the pit thus surrounded could hardly at 

 any time of the year fall below 45° or 60°. But 

 by the use of hot manure a temperatui-e from 60° to 

 100° might be got up and sustained around the pit. 

 This being so — and no one conversant with the 



Fig. 18.— Melon oe Pine Pit. Fig. 19.— Flat-roofed Pit, Lined. 



Heated by dung linings, a, I, pit ; c, c, linings. Shelving hoUow walls, and linings wider at top than bottom. 



not be nearly so deep as those for the culture of 

 Pines. A depth of from four to five feet is ample 

 for Melons where decomposing materials are wholly 

 depended upon for the supply of ai-tificial heat. In 

 cases where hot water is used, less depth is needed. 

 But for the culture of Melons, as well as Cucumbers 

 —and the pits for the one will answer equally as 

 well for the other — the mixed plan of heating — that 

 is, hot water and hot dung or leaves — is the best. 



Thoug'h the question of heating pits, and also 

 other structures, is reserved for separate treatment, 

 it is almost impossible to make our description of 

 Melon and Cucumber pits intelligible without re- 

 ference to linings, which provide the means of warm- 

 ing such structm-es. Melon and Cucumber pits are 

 mostly built of nine-inch brickwork, solid or pigeon- 

 holed, or fourteen-inch hollow walls. It is essential 

 that the walls should be strong, and that the pits 

 should be so constructed as to enable heat to be 

 thrown in from the outside to the inside of the pit 

 with ease and despatch. 



Linings are constructed for this express purpose. 

 These consist of spaces, two, two and a half, or even 

 three feet wide, running all round the pit at times 

 — always along the front and back where not all 



heating power of manm-o in a state of decomposition 

 will question the fact — the next structural point of 

 importance in regard to our Cucumber and Melon 

 pit.s is how to get this external heat inside the pits, 

 and a second question of almost equal moment is 

 how to regulate its amount so as to turn it to the 

 highest practical account. Heat can be forced 

 through a brick wall, but considerable waste is in- 

 volved in the process. Hence the origin of what are 

 called pigeon-holed walls, double walls, arched, pil- 

 lared, and other pits. Nearly all these aimed, more 

 or less successfully, at the solution of the compound 

 problem already stated, viz., the warming of Melon 

 and other pits by decomposing materials, and the 

 forcing of the heat into regularity and semi-per- 

 manency. 



The dung linings were, in fact, almost the only 

 heating furnaces known to our fathers. Their 

 covering shutters were the furnace-doors by which 

 they checked waste, and by cutting off the draught 

 regulated the production. The stable-yard, or heap 

 of Oak-leaves or tan, was their never-failing coal- 

 heap ; the vapour and heat of these materials, and 

 peculiar structure of their pits, their hot- water pipes, 

 tanks, &c. They had only these, and their achieve- 



