SEKD IMPROVEMi;NT MEETING. 229 



Rigidity, Strength and Smoothness of Walls. — An ideal silo 

 must have rigid walls. It must be strong enough to resist the 

 bursting pressure of-the silage. This acts outward in all direc- 

 tions as the silage settles. The friction of the silage against 

 the wall and the weight of the wall produce a crushing action 

 which is great near the bottom of the silo. A silo when empty 

 should be heavy enough to stand against heavy winds. The 

 inside of a silo wall should be reasonably smooth to permit 

 the silage to settle freely. If the wall is not smooth, or if 

 there are shoulders or offsets on the inside surface, air pockets 

 will be formed and a considerable loss of silage will result. 



Durability. — After due consideration to all other points of 

 merit to be found in silos, the most desirable silo is the one 

 that is the most durable and will give the longest term -of ser- 

 vice. The durability of a silo depends first upon its strength, 

 and, second, on the durability of the material used in its con- 

 struction. To be durable, any material must resist the action 

 of the weather, the constant wetting and drying, freezing and 

 thawing in the winter season, and any disintegrating action 

 which may be due to the silage itself. Some material will dis- 

 mtegrate with age, and other materials suffer from rapid decay 

 when subject to the warm, moist conditions which exist in the 

 silo. 



Care and Repair. — It is desirable that a silo require the mini- 

 mum expenditure in the way of labor and material for its up- 

 keep. A silo which must be adjusted for shrinkage and expan- 

 sion is of less value than one which does not need such atten- 

 tion. Often this work is neglected, and loss results. Some 

 silos must be frequently repainted in order to present a pleas- 

 ing appearance. This means added expense. All parts should 

 be equally durable and lasting. The replacement of parts 

 which are short-lived, the substitution of new pieces for those 

 which have become decayed or faulty for any other reason, 

 adds materially in many cases to the cost of maintaining the 

 silo. 



Convenience. — A silo should be convenient for filling, arid so 

 arranged that the silage may be easily removed from day to 

 day during the feeding season. The doors should be so con- 

 structed that they can be put in place and removed with the 

 least effort. They should permit easy access to the silo and 



