234 



FARM ARITHMETIC. 



crushed stone. It is richer in cement than is ordinarily 

 required. For walks, cellar floors, building walls, etc. 

 A 1-21/2-5 mixture is amply sufficient. For heavier work 

 the proportions may be 1-3-6 and for massive and unim- 

 portant work 1-4-8. 



Mixing. On a level watertight platform spread out 

 the measured quantity of dry sand and on top of this the 



Concrete Water Tank. 



cement. Turn dry with shovel until thoroughly mixed — 

 at least three times. Add the gravel or stone (thor- 

 oughly wet) and again turn at least three times, adding 

 water slowly, from a sprinkler, after the first time. Add 

 only enough water to make a thick mush, so that when 

 lightly tamped into place the water will just flush to the 

 surface. Mix small batches, one or two bags of cement 

 at a time, and, to avoid deterioration, place in the forms 



