432 PITS ANI 



The arched pit. — Of pits heated by fer- 

 menting material, we may notice the 

 following, as communicated to " The 

 Gardeners' Chronicle " by an anonymous 

 correspondent. This pit has the merit, 

 at least, of originality. It is thus de- 

 scribed :— " The length is 33 feet. There 

 are nine arches, separated by piers which 

 are only 9 inches square. The abutments 

 at the ends are only 18 inches by 9." 

 The ends and sides are similarly con- 

 structed. " It is divided into three com- 

 partments. The end walls and the 

 partitions are 9 -inch work up to the 

 level of the springing of the arches ; 

 above this line it is only 4J-inch work. 

 It is finished with a wooden coping, upon 

 which the sashes slide. The front arches 

 are about 2 feet 5 inches high ; those 

 behind, 2 feet 10 inches. The masonry 

 is carried up about 1 8 inches above the 

 arches in front, and about 1 foot more 

 behind. It is plastered inside, cow dung 

 being mixed with the mortar as in a 

 chimney. It is probable that the heat 

 from the outer lining of dung will more 

 thoroughly penetrate the mass inside 

 than it would do through the pigeon- 

 holes of the ordinary construction, as the 

 opening is very considerably greater in 

 extent, and it is more easily filled and 

 emptied when required." 



This pit is constructed entirely of brick; 

 but the same ends would be accomplished 

 were the piers of cast-iron, or stone pillars 

 used, and lintelled over with pavement 

 or cast-iron bars. Indeed we question 

 in the present day whether cast-iron 

 might not be introduced both for pillars 

 and lintels with greater economy; cer- 

 tain it is that less solid space would be 

 occupied by it. But the superstructure 

 should either be of wood or brickwork, as 

 stone, when exposed to the weather, is so 

 great a conductor of cold and damp ; and 

 plates of iron would be liable to objections 

 of another description. 



Baldwin' 's pine pit, fig. 597. — This is 

 one of the most economical of all pits. 

 It was at one time held in much repute, 

 and is still used by those who have a 

 command of stable litter, and in localities 

 where coal is expensive. It is thus de- 

 scribed in Baldwin's little work, "Culture 

 of Ananas," p. 1 1 : — " Sink your pit 3 

 feet 3 inches deep, and of such length as 

 you may require," (the usual dimensions 



FRAMES 



are 7 feet wide and 7 feet 3 inches high 

 at the back, the height of the front de- 



Fig. 597. 



pending on the angle of elevation desired,) 

 " and make it sufficiently broad to admit 

 of linings on each side. There should be 

 a good drain at the bottom of the pit to 

 keep it dry. Then set posts of about 6 

 inches square in the pit, at convenient 

 distances, (say about the width of the 

 sashes,) and case it round on both sides 

 of the uprights with l|-inch deal wrought 

 boards above the surface, and below 

 it with any inferior boards or planks." 

 These latter should not be more than 3 

 inches broad, and 3 inches apart from 

 each other — their use being to keep in 

 the leaves, tan, or dung, and also to ad- 

 mit the heat of the linings with as little 

 obstruction as possible. Such pits are 

 very useful, and may be erected at little 

 cost where timber is plentiful. They are 

 of all others the best adapted for tempo- 

 rary purposes. In damp situations, these 

 and all other pits should be built on 

 the surface, not under it; and as an 

 improvement on them, they should be 

 provided with gutters at front to take off 

 the rain water that falls on the sashes, to 

 save the material as well as the heat of 

 the front linings. 



One objection to this pit is, that the 

 linings are not enclosed to secure them 

 from the weather, by which a great 

 waste of dung takes place. Another im- 

 provement would be to substitute cast- 

 iron uprights for the present wooden 

 ones, and to enclose the bottom part with 

 f -inch wrought-iron rods, made to pass 

 through the uprights 3 inches apart, 

 instead of spurs of wood, for the purpose 

 of rendering them more durable, as 

 well as to admit more freely the heat 

 of the linings to the main bed. The 

 upper part of the pit we would prefer to 



