234 



FARM ARITHMETIC. 



crushed stone. It is richer in cement than is ordinarily 

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

 A 1-2^-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 



