ALL-METAL SILOS. 105 



struction forms a rigid reinforcement of the silo wall, and pro- 

 vides an easy and practical means of increasing the capacity of 

 the silo at any time, by bolting on additional sections to the 

 top. It also makes it practical to move the silo by taking the 

 sections apart and re-erecting them in another location." 



Mr. Charles P. Buck, writing for the Kansas State Board 

 of Agriculture in 1914, says: "The metal silos are made air- 

 tight by pealing the joints between the sections with a cement 

 of an elastic nature, unaffected by moisture, cold or heat. The 

 silo also is provided with a means by which the doors, through 

 which the ensilage is thrown down into the feed boxes, are 

 sealed absolutely air-tight, thus avoiding one serious cause of 

 spoilage and loss. 



"The two questions which usually arise regarding silos .con- 

 structed of metal are regarding the action of the silage juices 

 on the metal and the radiation of the heat of fermentation 

 through the metal wall. 



"Silage juice, after the fermentation, is slightly acid, con- 

 taining minute quantities of acetic and lactic acids. It is cus- 

 tomary to protect metal silos against the mild acids of this 

 juice by painting the interior with an asphaltum paint, which 

 forms a cheap, durable and reliable protection. 



"The question of the effect of radiated heat loss during fer- 

 mentation is best answered by the results obtained in the 2,000 

 or more metal silos now in use. In these it has been found 

 that the silage next to the wall is as thoroughly fermented and 

 as well preserved and palatable as that in the center of the 

 silo. There probably is some heat lost by radiation, but there 

 is apparently sufficient heat produced during the fermentation 

 to supply all that is necessary despite the radiated loss. 



"Practical use in the field has demonstrated that the metal 

 silo has every good quality which has been desired in a silo. 

 Once erected it is permanently air-tight and moisture-proof. 

 The form of construction so reinforces it that it is secure against 

 high winds, it requires practically no care or expense to main- 

 tain, and produces ensilage without mold or rot and consequent 

 loss. 



"Properly constructed metal silos need no guy wires, cables 

 nor anchors. They are secured in a foundation of concrete in 

 much the same way as are modern structural steel smokestacks 

 of immense height. 



"The leading manufacturers, have by careful experiments 



