PRESERVATION OF SILOS. 81 



If the silo is constructed outside, materials for roof and 

 painting are to be added to the preceding list. 



Although most of the foregoing descriptions of stave silos 

 do not mention tongued and grooved staves, the latest practice 

 indicates that, if properly done, it Is a decided advantage to 

 have the staves matched, also slightly beveled. The silo made in 

 this manner will not be so liable to go to pieces when empty. 

 This is the chief objection to the stave silo, and numerous 

 cases are on record where stave silos standing in exposed places 

 have blown over when empty. It is recommended, therefore, that 

 stave silos be attached to the barn by means of a feeding chute, 

 and in the case of hiigh or exposed silos it Is well to make use of 

 guy rods or wires in addition. Indeed, some manufacturers of 

 stave silos now recommend these on some of their silos, and 

 make provisions for them. 



Preservation of Silo. 



A silo building will not remain sound for many years unless 

 special precautions are taken to preserve it. This holds good 

 of all kinds of silos, but more especially of wooden ones, since 

 cement coating in a stone silo, even if only fairly well made, will 

 better resist the action of the silage juices than the wood-work 

 will be able to keep sound in the presence of moisture, high 

 temperature, and an abundance of bacterial life. 



In ease of wooden silos It is necessary to apply some ma- 

 terial which will render the wood impervious to water, and pre- 

 serve it from decay. A great variety of preparations have been 

 recommended and used for this purpose. Coal tar has been ap- 

 plied by a large number of farmers, and has been found effective 

 and durable. It may be piit on either hot, alone or mixed with 

 resin, or dissolved m gasoline. If it is to be applied hot, some 

 of the oil contained in the tar must previously be burnt off. The 

 tar is poured into an iron kettle, a handful of straw is ignited 

 and then thrown into the kettle, which will cause the oil to 

 flash and bum off. The tar is sufficiently burnt when it will 

 string out in fine threads, a foot or more in length, from a stick 

 which has been thrust into the blazing kettle, and afterwards 

 plunged into cold water. The fire is then put out by plac- 

 ing a tight cover over the kettle. The kettle must be kept 

 over the fire until the silo lining has been gone over. A 



