456 



PITS AND FRAMES. 



in which the melons are planted is sup- 

 ported in its position by strong slate, which 

 completely shuts out all moisture escaping 

 from the gutters, unless when the valves 

 are intentionally opened. Immediately 

 on the slates is laid a layer of brick-bats or 

 flints, at b, and over this some turfy loam. 

 Communicating with the rubble are small 

 tubes, through which the water can be 

 poured when any doubt arises as to the 

 roots of the melons suffering from dryness. 

 The water thus applied spreads itself over 

 the surface of the slate, producing that 



moisture so congenial to the roots, and 

 which forms in this mode of culture so 

 desirable an attainment, particularly as 

 the roots are only supplied with the pro- 

 per amount of moisture to maintain the 

 plants in luxuriance and health ; and that 

 this moisture can be withheld, when the 

 period arrives that a cessation of the sup- 

 ply of all fluids is desirable, to promote 

 the ripening of the fruit." — Gard. Chron. 



Fig. 642 is a section of one of several very 

 excellent pits, or rather low greenhouses, in 

 the royal gardens at Frogmore. Each divi- 



sion is 8 feet in height, and 13^ feet wide. 

 The plants are arranged on slate tables, 

 laid over brick chambers, in which the hot- 

 water pipes are placed, by which arrange- 

 ment a fine genial heat is afforded to the 

 roots of the plants. These houses are in- 

 tended for the culture, propagation, and 

 flowering of plants. The advantage of 

 their construction and arrangement will 

 therefore be obvious. 



A passage runs along the centre, and 

 another of narrower dimensions along the 

 back wall, over which is placed a broad 

 slate shelf supported on iron brackets, and 

 on which are placed the smaller plants, 

 and such as require to be placed nearest 

 to the glass. This shelf, as well as 

 the slate tables, is furnished at the side 

 with a very neat beading of slate, which 



prevents the water spilt in watering from 

 dropping on the footpaths. They also 

 answer another important end, namely, 

 being capable of holding water. The culti^ 

 vator has it in his power to command any 

 degree of humidity in the atmosphere he 

 chooses, or of allowing the plants to supply 

 themselves with water at their roots. Pro- 

 vision is also made by which this water 

 may be withdrawn when a drier atmos- 

 phere is deemed necessary. The plants 

 are arranged as will be seen by our fig., 

 so that they all equally enjoy the full in- 

 fluence of the light, and are nowhere too 

 far from the glass. Ventilation is effected 

 by the top lights sliding down, and gradu- 

 ated to any extent of opening by weights 

 and pulleys suspended along the back 

 wall. The front upright sashes are also 



