186 



FIXED STRUCTURES FOR GROWING 



width, and a door made in one end. The roof over the passage i8 

 generally opaque and sloping to the north, as in fig. 151. To the pos- 

 sessor of a small garden, and an amateur, this is a very desirable 

 description of pit, as in it he may grow almost everything, provided he 

 -p. - _, does not attempt too many 



kinds of culture at once. 

 The form is very economi- 

 cal, from there being as 

 much surface of pit as there 

 is covering of glass ; and the 

 interior is very comfortable 

 to work in, as the operator 

 need not stoop. If the 



ends were made of glass, it 

 Pit. with the roof over the path opaque. ,-, , 



would be an improvement, 



by admitting the morning and evening sun : it would then, however, 

 be entitled to be called a small house, instead of a pit. The sashes of 

 all pits used to be made to slide between rafters which are fixed to the 

 plates of wood, which form, partially or wholly, the copings to the 

 walls. Such pits as shown in fig. 151 are now often made with fixed 

 roofs, ventilated above, and in the front and back walls. There should 

 be a bolt to each sash for fixing it when shut, and also when let down 

 for giving air, in order that there may be no risk of its being blown 

 off by high winds ; and all the sashes ought to admit of being readily 

 taken off, for the purpose of taking out, and putting in dung, tan, or 

 other materials. When the pit is ten or twelve feet in width the 

 sashes may be in two lengths, the one sliding over the other ; the upper 

 sash sliding on ledges formed in the rafters, so as to render it indepen- 

 dent of the lower sash. In general, short sashes for pits last much 

 longer, and occasion much less breakage of the glass than long ones, 

 from their leverage being so much less. The roofs of all pits ought to 

 have coverings, and the best material, in our opinion, is boards, as, 

 where glass is so flat as it generally is in pits and frames, it is apt to get 

 dirtied by straw mats, unless these are put over a covering of bast 

 mats. Fig. 152 is an excellent plan of a pit or small house, with a 



Fig. 152. 



Ground plan of a pit to be heated in Mr. Corbett's 



a, Back path. 



6, Bark pit, 50 ft. long in 



the clear, 

 C, Exterior pit for dung 



casing, to revive the 



heat. 



d, d, Gratings to drains. 



e, Stink-trap to drain. 



manner. 



span-roof all of glass, designed by Mr. Glendinning, for general pur- 

 poses, and heated by Corbett's hot-water apparatus. Mr. Corbett's 

 system appears to be better adapted for pits than for larger and longer 

 houses, where its heating power would probably not be sufficient, or 



