46 Concrete Silos 



investigators have not been able to find an owner of 

 a concrete silo who would build a silo from any other 

 material. 



Relative to the action of acids on silos the publication 

 above quoted says: "It is very glibly stated by the 

 salesmen of wood stave silos that the acetic acid devel- 

 oped by the process of fermentation in ensilage corrodes 

 and e'ats away the concrete wall so as ultimately to 

 destroy it. This statement at first glance would seem 

 to have some basis of truth, for the reason that it is a 

 well-known fact in chemistry that acetic acid will attack 

 some of the materials of concrete wherever found, and 

 thereby produce acetates. This fact has been magnified 

 and has been used by wood silo men to damage the 

 reputation of concrete silos. But here is another fact: 

 The amount of acetic acid developed in fermenting 

 ensilage is so small and is so much diluted that it has 

 practically no effect whatever upon the concrete. Con- 

 crete silo after silo has been visited, some of them 

 having been in use for more than 25 years, and in no 

 case has the least evidence of the action of acetic acid 

 upon the silo wall been discovered. The walls are as 

 smooth and clear and clean after 25 years of service as 

 they were in the first place. 



' ' The greater initial cost of masonry silos is another 

 argument used against them by the wood silo men. 

 This argument might be made valid if the wood silo 

 men would put their price where it might be regarded 

 as reasonable. This fact, however, must be remem- 

 bered that the first year's loss on a wood silo that 

 blows down during the first year and has to be re- 

 erected amounts to more than the initial cost of any 

 masonry silo. The masonry silo, when properly re- 



