380 



A bricklayer should lay from 100 to 150 bricks per hour, 

 according to the nature of the work. 



Mortar : 100 of lime contains 25 striked bushels = 100 pecks. 

 One ton = 32 bushels. 



Eighteen heaped = 22 striked bushels = i cub. yard = one 

 load of sand. 



Two and a half to rive parts of sharp, clean sand to one of lime 

 for mortar, according to quality of lime. 



Or, i of lime to 2 of sand and A of blacksmith's ashes. 



Coarse mortar = r of lime to 4 of coarse gravelly sand. 



Concrete = i of lime to 4 of gravel and 2 of sand. 



One load of mortar = i cub. yard. 



One load of sand = i cub. yard. 



A road of brickwork requires from i^ to 3 loads of mortar. 



Portland cement : A bushel of cement weighs 67 Ibs., and a 

 barrel is 5 bushels ; a bag is 3 bushels, and a sack is 5 bushels. 



Equal parts of cement and sand are used for building purposes. 



Portland cement concrete for floors or walls : i of cement to 

 6 or 7 of broken stone, mill cinders, burnt ballast, shingle, gravel, 

 or slag ; must be from loam, mud, line sand or dirt of any kind ; 

 moulds to be soaped. 



Roman cement, only one-third the strength of the above. 



Mastic cement is i of red lead to 5 of w r hiting and 10 of sharp 

 sand, mixed with boiled linseed oil. 



One yard of reduced brickwork requires about 2] bushels of 

 equal parts of Portland cement and sand. 



One square yard of plastering with cement requires three- 

 fourths of a bushel. 



Concrete walls should be raised only 18 in. per day. 



Plastering : i cub. yard of lime, 2 yards of sand, and 3 bushels 

 of hair will cover 75 sup. yards on brick, or 70 yards on lath. 



One bundle laths and 500 nails will cover 4^ yards sup. 



McConnells Note Book. 



MORTAR Lime, as used for building purposes, is obtained from 

 several of the varieties of stone, marble, and chalk, termed lime- 

 stones. It is prepared by burning or calcining the stone, thus draw- 

 ing off the carbonic acid in which it abounds. After calcination 

 it is reduced to a white powdery material, which greedily takes up the 

 water ; it is then known as quick-lime. In making mortar, 

 fresh burned lime is taken from the kiln, and laid in a heap in 

 a convenient place, and, sprinkling a quantity of water on it, the 

 lime begins immediately to crack and iall down, steam issuing from 

 the heap in considerable quantities, a high degree of heat being at 

 the same time induced 6n the completion of the pn>ce>s of de- 

 composition, the lime is reduced to an impalpable powder, which 

 goes by the name of 'slacked' or 'slaked ' lime. The slacked lime 

 thus obtained is next to be well mixed with water, forming a paste, 

 and, afterwards, have the proper proportion of sand added two- 



