THE SOUTHERN PLANTER. 



99 



should not be slaked until it is about to be 

 mixed with the sand. The sand should consist 

 of angular particles of various sizes, perfectly 

 free from 'admixture with clay, mud, or earth 

 matter. This is spoken of technically as clean 

 sharp sand:, sea sand is not good'; because it is 

 difficult, even by washing, to free its particles 

 from saline matter, and they are also generally 

 rounded by attrition, which renders them less 

 fit to serve as a nucleus for the lime. The 

 effect of the saline matter remaining in the 

 mortar is to render the wall perpetually damp 

 by the absorption of moisture from the atmos- 

 phere. 



The proportions of lime and sand can only 

 be judged of by direct experiment. The lime 

 should be in such a quantity as to fill up prop- 

 erly the interstices between the particles of the 

 sand, and to .prevent them from being in abso- 

 lute contact with each other. A good approxi- 

 mate rule may be found by filling any vessel 

 with sand, and then adding water until the 

 voids between the particles of the sand are 



is described as being so many bricks in thick- 

 ness ; thus, a nine inch wall is a wall of a sin- 

 gle brick in thickness, or one brick thick ; a 

 fourteen-inch wall is a brick and a half, and 

 so on. 



In bricklaying the main points to be ob- 

 served are the bond and the plumb of the wall. 

 Bond in brickwork, signifies that disposition 

 of the bricks by which the joints of one course 

 are covered by the bricks of the course above 

 it, so as to make the whole aggregate of bricks 

 to act together and be mutually dependent on 

 each other. Fig. 57 shews this in its simplest 



Fig. 57. 



fortfc, where A represents 

 sides of one course of bricks 



the longitudinal 

 B the course im- 



mediately above, and C a third course, with its 



filled and its service covered; the bulk of joints recurring over those of A, while the 

 water will then serve as a pretty fair guide to joints of B. occur in the intervals, and thus 

 the quantity of lime required. In practice, a i they give their conjoined suppoit to any super- 

 fair proportion is two parts sand to one of lime, incumbent weight. This is termed breaking the 



with as much added as will make the mass of 

 a pasty consistence. Some qualities of sand 

 require much more lime than this, even so 

 much as four and six parts of sand to one of 

 lime. The common practice of builders, how- 

 ever, is to err on this side, adding almost inva 



joint, and the recurrence of the vertical joints 

 in the same straight line in each alternate 

 course is called keeping the perpends. By the 

 simple arrangement shewn in the figure, verti- 

 cal and longitudinal bond is produced, and the 

 result is a well bonded wall of four and a half 



riably too much sand, to the deterioration of, inches, or hatf a brick thiclfc If the bricks 

 e mortar. • I vvere placed with their length across the wall, 



In mixing the sand and lime, the endeavorja nine inch wall would then be formed, but the 



longitudinal bond would be shortened one-half; 

 and it a Avail of greater thickness were re- 

 quired, it could only be obtained on such a 

 system of building, by repeating an indepen- 



should be to obtain as homogeneous a mass as 

 possible; and if the lime, from any defect in 

 its quality, or from improper calcination, is not 

 converted into an inpalpable powder by sla- 

 king, but, on the addition of the water, breaks 'dent brick or half-brick wall alongside of' the 

 into small lumps, it will not make a good j other, without lateral connection, 

 mortar unless it is ground previously to the I Bricks laid lengthwise in the direction of 

 sand and water being added y for the lumps of (the walls, as in Fig. 57, are termed stretchers, 

 unslaked lime, existing in the mortar, after j a nd it is only by a proper combination of 

 having^been some time in ^ wall, will he i headers and stretchers that -complete bond can 



be obtained. Fig 58 shews the arrangement. 



Fig. 58. 



gradually slaked, and, expanding in the process 

 will force the joints and dislocate the materi- 

 als of which the wall is composed. .When the 

 mortar is made, it should be kept in a pit or 

 close place, and protected from the action of 

 the air. Mortar thus kept is found to improve 

 by age, and when required for use it is taken 

 out in such quantities as may be wanted, and 

 beaten up with as much water as will make it 

 work as freely. 



Bricklaying. — The average size of bricks in 

 this country is nearly nine inches long, four 

 and a half jnches wide, and two and a half 

 inches thick; the proportion of length and 

 width, the former being twice the latter, has 

 much to Ho with the method of disposing the 



of bricks in a brick and a half, or fourteen 

 inch wall, A, shews a course consisting of a 

 row of stretchers a, a, and a row of headers b. 



brick in the wall. The determinate size of! 6. B, shews the course immediately above, in 

 the brioks, too, serves as a convenient measure | which the disposition of these is reversed, the 

 to denote the size of a wall, which, in general, I header being now on the side occupied by the 



