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necessary the sand and stone piles must be protected 

 from the sun. 



Placing Concrete. No concrete must be placed in 

 any form unless the inspector has personally assured 

 himself that the form has been cleaned out and the 

 abutting surfaces of concrete have been properly pre- 

 pared to make a bond with the new work. Be sure 

 also that no foreign substances have become lodged in 

 any portion of the form or reinforcement. 



Each batch of concrete must be in place within 

 twenty minutes from the time it is discharged from 

 the mixer. 



Concrete must not be deposited in any portion of 

 the work until all of the reinforcement for that part 

 of the work are in position and have been checked over 

 to see that they agree with the drawings. The steel 

 work must be kept sufficiently ahead of the concrete 

 work to give ample time for inspection. 



No lumps of concrete must be permitted to lie in 

 any of the cars, hoppers, troughs, wheelbarrows, or 

 other receptacles which are used for conveying it from 

 the mixer to the form. Each receptacle must be 

 cleaned at the cessation of work. 



The concrete inspector must note carefully the uni- 

 formity of the mixture delivered to the forms and see 

 that it contains no foreign substances. He should be 

 careful to note whether the color apparently indicates 

 the proper mixture and in cases of doubt must verify 

 from the mixer the proportions of the batch. 



Each beam and slab must be completed monolithi- 

 cally. No portion of the work must be started unless 

 it can be pushed to completion, except by special per- 

 mission of the engineer. 



In filling the forms, care must be used to spade the 

 stones back so that a mortar finish will be secured. If 

 called for in the specifications facing mortar must be 

 deposited simultaneously with the concrete. The fac- 

 ing mortar can be held in position until the backing of 



