FARM MANAGEMENT 147 



the molds after they have been used five or ten times, or as often as 

 necessary, will prevent the concrete from sticking. 



Reenforcement is steel in the form of bars, rods or wires, buried 

 in concrete to take up and to withstand the strains which tend to 

 stretch or to bend the concrete. A concrete fence post is merely a 

 small concrete column. Reenforced, it easily stands the strain from 

 usage in a fence line. 



Reenforcing should be placed near the outside wall, where it is 

 reasonable to expect that cracks will open. For reenforcement, metal 

 slightly rusted is as good as metal that is not rusted, if not better. 

 In placing the reenforcing rods in position it is a wise precaution to 

 bend them back at the ends. This takes only a little more time, 

 but, if it is done, the reenforcement must be 2 inches longer to allow 

 the metal to be turned back 1 inch at each end of the post. New 

 barbed wire should not be purchased for reenforcement. 



The danger section, or the point where posts are liable to break, 

 is at the surface of the ground. For fences for lots and other places 

 where posts may be subject to rubbing and crowding, short extra 

 reenforcing pieces 2 feet long are sometimes placed in the post to lap 

 this danger section. The corner of triangular-shaped posts which 

 is not nearest the fence wire should, in theory, have heavier reen- 

 forcement than either of the other corners. If rods three-sixteenths 

 of an inch in diameter, No. 8 wire, or two twisted No. 12 wires, are 

 used in the other corners, a rod one-fourth of an inch in diameter, 

 or two or three twisted No. 12 wires, should be placed in the threat- 

 ened corner. (Col. Exp. Sta. B. 161; F. B. 403.) 



Molding. After the molds, which, as a rule, lie flat, have been 

 oiled or soaped, the concrete should be placed in them at once. If, 

 for any reason, the concrete stands thirty minutes after mixing, it 

 should be thrown away and a new batch mixed, for cement, if it has 

 once partially set, makes weak, dangerous concrete, even though it 

 is retempered by turning or adding water. After the molds are filled 

 evenly to the depth of three-fourths of an inch or 1 inch, according 

 to the spacing of the reenforcing rods or wires, the reenforcement 

 should be laid in, properly spaced. The concrete should then be 

 poured in until the molds are filled within three-fourths of an inch 

 or 1 inch from the top, when the remaining reenforcement is fitted 

 in place and the molds are completely filled. To render concrete 

 more compact, a crowbar or a pinch bar should be placed under 

 each corner of the mold successively and moved up and down quick- 

 ly. This vibration makes the concrete more compact by shaking 

 out the air bubbles, but there will be very few of these bubbles if the 

 concrete is sufficiently mixed to proper consistency. If desired, the 

 exposed corners of the post may be beveled with an edger and the 

 open face given a neat finish by using a trowel immediately after the 

 surface water has been absorbed and before the concrete has become 

 too hard. 



If wooden molds are used, they should be well soaked in water, 

 so that the green concrete will not cause them to swell and thus 

 crack the posts. The wind, the hot sunshine, and the frost are de- 



