98 



GARDEN WALLS. 



course of bricks should be laid across, 

 under the surface, as in fig. 97. In fig. 



Fig. 97. 



96, c is a 

 cross sec- 

 tion, and 

 d a por- 

 tion of 

 the cast- 

 iron up- 

 r i ght, 

 with the 

 bricks 

 placed in 



its grooves. These bricks lock into one an- 

 other, and thus may be put together and 

 stand without cement ; or they might be 

 merely dipped into thin grout before lay- 

 ing together, and thus their staunchness 

 insured. Rebated bricks of this kind 

 would be as easily made as common ones ; 

 and the rebate, like that of a sash, would 

 prevent water from flowing through. The 

 bottom course of bricks should be laid 

 across, under the surface, as in fig 97, to 

 form a broad foundation." 



All walls constructed of pavement, 

 slate, glass, &c. being of course narrow, 

 if not built double, with a solid or hollow 

 centre, will require a coping, both for ef- 

 fect, and for the protection of the trees 

 that may be trained upon them. This 

 can readily be added by employing the 

 same material. Walls thus constructed 

 are considered to be of all others the most 



Concrete walls are of great antiquity. 

 They are constructed as follows : The 

 excavation for the foundation — the latter 

 being also of concrete — is made to the re- 

 quired depth and width. The depth in 

 this case depends on the subsoil in a 

 much less degree than where no concrete 

 is used — and hence the great utility of 

 concrete in situations where a solid basis 

 cannot easily be reached ; for, within a 

 few days of its being finished, it becomes 

 united together into one solid mass through- 

 out its whole length and breadth. When 

 the foundations are brought to their pro- 

 per height, a strong framework of plank- 

 ing should be made on both sides of the 

 intended wall, and exactly as far apart as 

 the thickness of the wall is designed to 

 be. The greater the length this frame- 

 work is, the better — as, by the time the 

 operation of filling in the concrete has 

 arrived at the end, the planks at the part 



first done may be ready for removal, and 

 for setting a course higher : this, however, 

 should not be attempted until the con- 

 crete has become fully set. The frame- 

 work is then to be lifted up for another 

 course, which course should be only about 

 1 8 inches thick. This process is continued 

 till the entire height of the wall is done. 

 When the frame is set, gravel, just as it 

 comes from the pit, and pretty coarse, is 

 laid within the frame to the depth of 4 

 inches ; hot lime grouting is then poured 

 over it in sufficient quantity to cement 

 the whole together ; and the same pro- 

 cess is followed till the wall is finished. 

 When thoroughly dry, any cavities on the 

 surface may be made good, and the whole 

 rough-cast, plastered, or cemented, ac- 

 cording to circumstances. Such walls 

 should be coped with stone, brick, or 

 other similar material ; for, like all other 

 walls, the dryer they are kept the better. 

 The proportion of hot lime to the gravel 

 is about one-eighth part only, although 

 some make the proportion one to five, 

 particularly where loamy gravel is used. 



The Chinese construct concrete walls 

 much in the same way as described above, 

 only using sifted sand and quicklime in 

 the proportion of about 15 to 1. 



Clay walls. — Denson, in "The Peasant's 

 Voice," (p. 31,) describes a mode of build- 

 ing mud walls practised in Cambridge- 

 shire as follows : When a sufficient 

 quantity of clay is dug, it is wrought up 

 with straw, and moulded in a frame 18 

 inches in length, 6 deep, and from 9 to 12 

 inches in diameter, in the same manner as 

 the brickmaker moulds his bricks. The 

 lumps thus formed are dried in the sun, 

 and, when sufficiently hard, are laid ex- 

 actly like bricks, and jointed with mortar. 

 The foundation is formed of stone or burned 

 bricks level with the ground surface; and 

 when finished, the wall is plastered or 

 roughcast over, which gives it a clean 

 and neat appearance. Such walls are 

 usually coped with thatch, with broad pro- 

 jections on both sides to keep them dry. 



Cob walls are the mud walls of Devon- 

 shire, where they are common both for 

 garden walls and even for respectable- 

 looking two-storey houses. A house of 

 this description was pointed out to us last 

 year, said to be upwards of two hundred 

 years old. The construction of cob walls 

 is thus described in the " Encyclopaedia 



