DECORATION OF HOME GROUNDS 83 



The directions for mixing cement concrete are the 

 same as for concrete buildings which was described on 

 page 68. Upon a steep slope the surface of the concrete 

 should be ribbed to prevent slipping or the surface 

 covered with boards in icy weather. For the foundation 

 of a cement concrete walk a dry mixture of from 

 four to six parts of sand and course gravel to one 

 of cement, from four to six inches thick, is thoroughly 

 tamped so as to be smooth and level. Then a layer 

 of one to two inches of concrete, two or three 

 parts of sand to one of cement, thin mixed, so 

 as to work easily, is spread over the surface and 

 made smooth. To prevent the concrete from cracking 

 irregularly by the action of frost from below, it is some- 

 times made in squares or sections with a thin board 

 between the sections to take up the contraction and ex- 

 pansion. After laying cement concrete it should be kept 

 moist until fully set by covering with hay, straw, mats 

 or even sawdust, or by sprinkling two or three times. 



With tar concrete the first layer from four to six inches 

 thick of coarse stones from one to four inches in diameter 

 must be made solid by tamping or rolling as for the 

 foundation of cement concrete, as well as the two suc- 

 ceeding layers of small stones. The last layer is of fine 

 clean sand and hot tar, thoroughly saturated and mixed, 

 heavily rolled and then covered with fine dry sand until 

 somewhat hardened. Concrete walks have the advan- 

 tage that they may be easily kept clean in summer or 

 winter and no weeds will grow upon them, but they are 

 often slippery in icy weather and reflect the heat during 

 the summer. 



Screen the Walks and Drives With Shrubbery. 



Where walks and drives are wide and of considerable 

 length they should in part at least be covered from view 



