TANK FOR CUCUMBERS AND MELONS. 81 



inches to be divided into two parts for the floor, because 

 the floor must butt up to the work of the pit, covering 

 all the work of the tank. This gives a division of two 

 feet seven and a half inches for each slate or tile, each 

 one reaching from the walls of the pit half-way on to 

 the division c, and lying quite close side by side, no 

 steam to hurt will get through. The tiles or the slates 

 should be from one inch to one and a half inch thick. 

 It is waste of money to make the floor of wood, as the 



FIG. 20. THIRTY-FEET SECTION OF A SIXTY-FEET MELON PIT. 



References to pit. a a, ground line ; B B B B, water in tank ; c, brick division run- 

 ning the whole length, for flow and return hot water; UDD, floor on which the 

 soil rests for the plants. 



steam soon destroys it, but the slates or tiles will last 

 a lifetime with care, i.e. if not jumped on, &c. 



The tanks, i.e. one flow and one return, should be 

 on a level except a few feet at the cold end approaching 

 the boiler, which should be on a fall towards it a few 

 inches but not too much ; the boiler is always fixed 

 considerably below the level of the bottom of the tank, 

 so that the water flows rapidly into it. If a very rapid 

 circulation of hot water is required; some fall towards 

 the boiler from the far end of the return tank is neces- 

 sary ; but remember that the waste of water and the 

 wear and tear of the tanks is more. 



