CONCRETE 



141 



Place the mixing platform as level and firm as possible, 

 convenient to the supply piles of material. Place the 



^ 



• 1 I 



Fig. 136. 



£X6 s/f/<fcJ 



Details of construction of a mixing platform 



3 



measuring box on the platform and measure 2 cubic feet 

 of sand. Remove the box and spread out the sand in a 

 layer about 4 inches thick. Spread one sack of cement 

 uniformly over the sand. Start shoveling this pile into 

 another pile immediately back of one end of the original 

 pile with a turning motion of the shovel so as to mix the 

 sand and cement. Proceed straight through the original 

 pile and then turn around and start where you left off and 

 go back through the new pile in the same way. Go through 

 at least three times. A greater number is better. Next, 



