CHAPTER XXV 



Construction, Farm Engineering, Mechanics 



Farm engineering is concerned with layouts, and the projection of 

 physical enterprises on the land, — as surveying, laying out drains, 

 irrigation works, roads, bridges, and the like. Farm mechanics has to 

 do with construction, and the principles of physics underlying it. 

 Farm machinery as a department of knowledge has to do with the 

 application of mechanics to those devices known as machines. 

 Farm architecture is concerned with the building of barns, residences, 

 and other housing structures. 



Silos 



Least number of dairy cows that should be fed from silos of given diameters 

 (Rawl and Conover) 



Feeding capacity of silos (Wis. Sta.). 



When the cows are getting 40 pounds of silage daily, each cow 

 should be allowed 4 to 5 square feet of feeding surface in the silo. 

 Ten cows would require a feeding surface of 50 feet. A silo 8 feet in 

 diameter would have a cross section, or feeding surface, of 50 square 

 feet. For 10 cows, therefore, a silo should be 8 feet in diameter. Fif- 

 teen cows should have a silo 10 feet in diameter ; 20 cows should have 

 a silo 12 feet in diameter. The diameter of silos required for different 

 numbers of cows is shown in the following table. It is assumed that 

 each cow eats 40 pounds of silage daily. 



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