CHAPTER IV 



BOND --BRICKWORK — HOLLOW BRICK WALLS— STONEWORK 



Bond. — Brick, and also stone walls are built with due regard to the 

 proper bonding or interlocking of the component bricks or stones, in 

 order to form a strong and stable structure. The word "bond" is used 

 to denote the laying of bricks or stones so as to avoid the occurrence 

 of continuous vertical joints. Bond is much more definite in brick- 

 work than in stonework, hence the former will be described first, and 

 the principles enunciated can be considered to apply, in a modified 

 degree, to stonework. 



Brickwork. — All walls settle, or subside, somewhat, after having 

 been built, due to the compression of the mortar while it is still 

 comparatively soft. If this settlement occurs irregularly, i.e. if one part 

 of the wall settles more than, or at a different time from, adjoining 

 parts, cracks known as "settlement cracks" are formed. In order to 

 insure more or less regular and contemporaneous settlement, and thus 

 avoidance of the above evil, three points require attention, they are : — 



1. The mortar joints should be thin, not exceeding § inch in 



thickness in the case of brickwork. 



2. Horizontal joints should be of uniform thickness. 



3. In building the wall be careful not to advance any one part 



in height much beyond adjoining parts, but raise the wall 



more or less uniformly along its whole length. 

 All joints should be completely filled with mortar. In order to 

 effect this, especially in the case of the joints in the middle of the 

 thickness of a thick wall, grouting is commonly resorted to. By 

 " grouting " is meant the pouring of mortar, thinned with water, into 

 the joints in question. 



Each brick is thoroughly wetted immediately before being laid, to 

 prevent too rapid drying of the mortar, and to remove any dust, from 

 the surface of the brick, which would prevent proper adherence of the 

 mortar. 



