FENCES, WALLS, AND SHELTERS. 



S5 



201. An economical wall is sometimes constructed of a brick in bed, or 

 stretcher, on each side, the space between being filled up with concrete 

 similar to that prepared for the foundation. This adheres 

 1o the brick-work ; headers, or bricks across, being used 



occasionally as bonders, to hold the two 

 sides together. A solid wall of 14 inches, 

 or even 18, which would require 3,620 bricks 

 to the rod, would thus only require 1,210, 

 while the cost of the concrete is compara- 

 tively trifling. In countries where brick is 

 not easily come by, a very good wall may be 

 constructed with a brick in front and stone 

 behind, where one front only is requir-od 

 '^"'^^^'^^^ for use. 



202. The introduction of hollow bricks is supposed to be conducive to dry- 

 ness and free ventilation, while it greatly reduces the pressure on the founda- 

 tion ; but it docs not appear that we have any great experience as to its result 

 on garden walls. 



203. Stone walls for gardens should be built in courses of four or eight 

 inches thick ; the stones ashlar or hammer - dressed, the joints chisel- 

 dressed, the mortar-bed 

 not too thick, and the 

 joints pointed and drawn 

 clean. In stone walls — 

 perhaps in brick walls also 

 — copper or iron nails with 

 eyes should be let into the interstices of the wall, to tie down 



the branches of the fruit-trees, taking care that they are let in with the eye 

 close to the wall ; for the radiation of heat from the wall is in proportion 

 to its distance, and the heat which is one degree a foot off the wall, is, as we 

 have seen, a hundred and forty-four when in contact with it. The advantage 

 of the eyed nails consists in preserving the wall. Thread dipped in pyro- 

 ligneous acid, or flexible wire, may be used for the purpose. The shred-and- 

 patch mode of training the young shoots will surely never again be used upon 

 a new wall. 



204. Hollow walls are only found in gardens of lofty pretensions, where 

 very high cultivation is adopted ; and we have reason to believe that in many 

 quarters where they exist, they are rarely used. Mr. Henry Bailey, 

 Mr. Harcourt's gardener at Nuneham, supplies us with very good reasons 

 for their use, however ; and certainly, where expense is no object, every 

 gentleman would like to see his walls covered with fruit in its season. 

 " Apricots," says Mr. Bailey, ''when placed on a south wall, are soon excited 

 by open sunny days in spring : the sap-vessels become filled with watery sap. 

 In this state, if a severe froat occurs, the sap-vessels are burst by the freezing 

 fluid, and the whole economy of the plant deranged. Some parts of the treo 



