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CHEMISTRY OF FARM PRACTICE 



194. Placing the Concrete. Concrete should be placed 

 immediately after mixing. Wooden forms to give the shape 

 of the structure to be built, Fig. 81, are required and should 

 be ready before the concrete is mixed. In placing the 

 concrete, the shovel should be run down along the face of 

 the form to press the gravel back and allow the cement to 



FIG. 81. Forms for concrete watering trough, 

 cultural Drafting.") 



(From Howe's "Agri- 



flow against the form, thus producing a smooth and finished 

 surface when the form is removed. 



New concrete should not be exposed to the sun until 

 after it has hardened for five or six days. The forms should 

 be left in place till the concrete has " set " thoroughly. 

 To permit removal of the forms, the surface should be wet 

 daily. 



