466 



THE VILLA GAKDENER. 



use in hot-houses, when we saw them in 1831, when the frames in question were 

 in full employment at both places. 



509. Protected walls are of various kinds, some being protected by 

 canvas curtains, and some by moveable glass frames. 



510. Conservative wall protected by curtains. Fig. 329. shows part of a wall 

 of this kind at Chatsworth, which has been found to answer extremely well. 



329 



It is divided into panels, about 27 ft. in length, and 18 ft. in height, rising 

 one above another, and divided by stone piers. The wall is flued, and covered 

 with a wooden trellis. It has a coping, which projects about 1 ft. in front, 

 with rods under it, on which the rings of the curtains run. Each panel 

 has a separate rod with two curtains, which open in the middle, and draw 

 back like window-curtains in the day, but are closed at night. The cur- 

 tains are of stout hempen cloth ; and in order to provide for the contrac- 

 tion and expansion in wet and dry weather, and also to keep the curtains close 

 together, the lower edge of the curtain is furnished with rings, which are put 

 over hooks fixed on the edge of a board, which lies flat on the border, at the 

 distance of 13| in. from the wall. The outer edge of this board, which is 

 11^ in. wide, is hinged to a rail 4^ in. broad, which is made fast to stakes 

 driven into the ground, and sawn oif level with the surface. In consequence 

 of this arrangement, when the wet weather contracts the curtains, instead of 

 shrinking up, and exposing a part of the wall to the weather, it merely lifts 

 up the inner edge of the board, which sinks down to its place again with the 

 return of dry weather. The edges of the curtain, next the piers, are made 

 fast to slips of wood fixed to the wall, and the edges where the curtains join 

 in the middle, overlap each other, and are tied or buttoned together, if the 

 weather is severe. Fig. 329. is an elevation of part of the wall, showing the 

 piers (the one rising higher than the other, as the wall ascends a sloping sur- 

 face), and the curtains drawn aside. 



Fig. 330. is a ground plan of the same portion of the wall ; in which a is 

 the dug border ; b, the rising and falling board ; c, fixed boards opposite 



