THE SOUTHERN PLANTER 



101 



lowest courses are made much wider than the 

 superincumbent wall, and this width is dimin- 

 ished in each successive course, by equal steps 

 at each side, until it is reduced to the proper 

 thickness of the wall. These steps are termed 

 the footings : they should not be more than a 

 quarter brick wide. The width of the footings 



Fig. 62. 



is, of course, dependent on the nature of the 

 foundation, and the height and consequent 

 pressure of the superstructure. The practical 

 rule for walls of moderate dimensions, under 

 ordinary circumstances, is to make the lowest 

 course twice the width of the wall, as in 

 Fig. 62. 



When a wall is more than a brick thick, two 

 men should he employed at the same place, 

 one on the inside, and one on the outside ; and 

 they should be equally good workmen, although 

 the general practice is to place an inferior 

 workman or apprentice on the inside. 



To make the attachment between the bricks 

 and mortar as perfect as possible, the bricks 

 should be well wetted before they are laid, so 

 that their pores may be freed from dry dust or 

 any dry matter which may prevent the adhe- 

 sion of the mortar ; it is also of great advan- 

 tage, for the same reason, to damp the upper 

 surface of the course of bricks last laid, before 

 spreading the mortar upon it. If these pre- 

 cepts are attended to, and the brick, in place 

 of its being merely laid on its bed, is pressed 

 into the mortar with a rubbing motion, the 

 lime will be forced into its pores, and perfect 

 adhesion will be the result. 



Mortar, although employed to produce ad- 

 hesion between the bricks by its cementing 

 power is, when used, a soft yielding material, 

 and if employed in too great quantity, will be 

 ressed out of the joints by the superincum- 

 ent weight, and the walls will not only settle, 

 but are apt to bulge and fall out of the plumb: 

 The mortar, too, from being pressed out of the 

 joints unequally, causes another evil; if it be 

 pressed out of the joint at one side, the joint 

 there will close and open at the other side, the 

 mortar then retiring within the line of the 

 wall, will form a channel or groove, which 

 trickles down the wall, first retains, then 

 absorbs it, and the first frost bursts and crum- 



bles the mortar, and the joint thus requires 

 constant repointing. For the same reasons 

 then, the mortar in the joints should never be 

 in greater quantity than merely to prevent the 

 absolute contact of the bricks; and, as a gene- 

 ral rule, no joint should much exceed one 

 quarter of an inch in thickness ; or, as it is 

 more commonly expressed, four courses of 

 brick-work should not measure more than 

 eleven and a half inches in height ; but as 

 bricks are generally a trifle under two and a 

 half inches thick, it is safer to limit the height 

 to eleven inches. 



While it is necessary to guard against the 

 common error of workmen, the putting of too 

 much mortar in the beds or horizontal joints 

 of brick-work, it is of still greater importance 

 to caution against another more common error, 

 the leaving the vertical joints without mortar. 

 It has been stated, that the workman, in laying 

 the bed, strikes off the mortar which projects 

 over, and spreads it on the end or side of the 

 brick last laid, and that is generally all which 

 the vertical joints receive. Hence has arisen a 

 practice of running in the joints of each course 

 with lime, in a fluid state, or grout, as it is 

 termed. This, however, can only be an imper- 

 fect remedy for bad building, being in itself 

 objectionable, on account of its hydrostatic 

 pressure being apt to burst the walls, and its 

 excess of moisture retarding the drying and 

 binding of the work. The true method is to 

 make the workman fill the vertical joints with 

 mortar, and this, which is generally termed 

 flushing, "can be done with an amount of labour 

 which the greater stability given to the work 

 will doubly compensate for. 



From what has been said regarding the set- 

 tling and other injury accruing to walls from 

 the yielding of the joints, it must be apparent 

 that a facing of stone to a brick wall must in- 

 jure its strength, as, besides the impossibility 

 of perfecting the bond, the former, containing 

 fewer joints than the latter, must yield less to 

 pressure, and cause fracture. A facing of 

 bricks rubbed smooth, for appearance sake, is 

 likewise objectionable, as the rubbing slightly 

 diminishes their size- 



It is a common practice among bricklayers 

 to carry portions of a wall to a considerable 

 height before beginning to the adjoining parts, 

 the result of which is, that the part first car- 

 ried up settles and comes to its bearing before 

 the adjoining part is connected with it, and 

 irregular subsidence and cracks ensue. This 

 practice should not be allowed, but the walls 

 should be carried up as nearly level as possi- 

 ble throughout. 



Arches in brick-work are formed either with 

 the bricks cut to a wedge form, when they are 

 called rough arches, or with the bricks uncut, 

 in which case the rectangular form of the 

 bricks is supplemented by a wedge-shaped joint 

 of mortar, when they are called plain arches, 

 or the bricks are not only cut, but gauged to 



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