farmers' institutes. 239 



thus cut out nailed together with some barrel staves, the staves giving 

 the short pieces the necessary curve to circle. The bevel must be on 

 inside of silo, so that when doors are set the silage will press them into 

 place. No frames for doors are necessary and no fastenings or hinges. 

 In cutting out the doors they should be numbered so they will be put 

 in the same place each time. A door 20 inches by 2 feet is large enough. 

 To cut out these places it is best to cut side bevel piece while the 2x4's 

 are on the ground. To do this, bore a hole in center of the 2x4 on 

 right bevel and cut with a tenant saw far enough to allow larger saw 

 to enter cut ; when piece is cut out, tack in place with some small nails. 

 Now finish up silo walls, and then the man in silo will have to cut out 

 the lower door in order to get out. If on outside, can cut his way in. 

 Doors must be about 3 feet apart to be handy in taking out silage. 



The hoops for this silo should be of five-eighths, round iron ; each 

 section of hoop should be long enough to pass through two of the 4x6 

 timbers, and threads should be cut 6 or 8 inches on each end of hoops 

 so as to take up any shrinkage of silo. Large cast iron washers are 

 necessar}^ to bear against the 4x6. Light washers will sink into the 

 w^ood when the silo is full and pressure bears on hoops. Hoops should 

 be placed as follows : First, one near bottom of silo about 6 inches from 

 sill ; the next 2 feet higher, and each alternate hoop 6 inches higher 

 than last put on. This is for 18, 20 and 25-foot in diameter silos ; smaller 

 ones may use fewer hoops and even one-half inch hoops will answer. 

 Our silo is now ready for roof. The roof of silo can be built of boards 

 put on hip roof style, or a cone-shaped roof can be put on and shingled. 

 Metal roofing is used by many, while many have no roof. I have used 

 silos without a roof and saw no bad results. 



SOIL IMPROVEMENT. 



(By Prof. R. \V. Clothier, Cape Girardeau, Mo.) 



Any discussion of soil improvement that attempts to enter into the 

 scientific principles involved in the process must begin first with a study 

 of the nature of soil physically and chemically. 



PHYSICAL STRUCTURE AND CHEMICAL COMPOSITION. 



The basis of all soils is ground rock. With this is mixed decayed 

 vegetable and animal tissues, called humus, in varying proportions. All 

 soils, then, whatever their nature and appearance, are composed of 

 ground rock mixed with more or less humus. A mechanical analysis 



