A CJiapter on Greenhouses. 



323 



den. The usual size of these pits would be twelve feet in width, and from 

 thirty to fifty or more in length, as may be desirable. 



As will be seen by the ground-plan, it has one path in centre, with a 

 broad shelf on each side ; the height of the shelf to be governed by the 

 purpose for which it is used. 



Select a position where perfect drainage can be had. Excavate the soil 

 three feet deep ; lay a ten or eleven inch hollow wall of brick three feet six 

 inches high ; frame the two upper courses into an eight-inch wall, with a 



course of headers at top ; have the inside line of the wall straight and true, 

 letting the set of the brick-work be on the outside. Or, if it is desirable, 

 a row of posts can be set, ceiled up on both sides, and the space between 

 filled up with tan-bark or saw-dust. This will leave the walls six inches 

 higher than the ground, which should be graded up nearly to the sill, that 

 the water may be carried freely from the building. 



The roof, being of one-quarter pitch, gives a rise of three feet in centre. 

 For No. I elevation, this will give sufficient height to pass freely in the centre 

 of the house. Elevation No. 2 will, of course, give more height. The en- 

 trance is at the ends, for which a series of steps is provided outside. 



