AGRICULTURAL ENGINEERING 277 



many silos and knows just how to do it. If a man is a 

 good mechanic, or can hire a good mechanic who has 

 had experience in building silos, he can usually save some 

 money by buying his materials and building the silo him- 

 self; but, if a good mechanic is not available, it is much 

 better and safer to buy some good patented silo. 



Size of Silo. — Like other buildings, the silo must be 

 planned to fit the needs of the farm. A cow will eat from 

 30 to 40 lbs. of silage per day. Other animals, like calves, 

 sheep, steers, etc., will eat about the same amount in propor- 

 tion to their weight. Ten 100-lb. sheep, one 1,000-lb. 

 steer, or four 250-lb. calves will eat about the same amount 

 of silage as a 1,000-lb. cow. One can tell about the number 

 of animals on the farm and the number of days during the 

 year they must be fed, and from that determine the number 

 of tons of silage likely to be needed. There are plenty of 

 books and bulletins that give the capacity of various sized 

 silos, or one can figure out the approximate capacity quite 

 easily by finding the number of cubic feet in the silo and 

 multiplying this by 40, as a cubic foot of silage will weigh 

 about 40 pounds. It is advisable to build a silo sufficiently 

 large. A tall, narrow silo is more satisfactory than a low, 

 wide one, because the deeper the silage the more it becomes 

 packed on account of the pressure. The more silage is 

 packed the better it will keep. The top of the silage in a 

 silo is always exposed. If a silo is narrow there is less sur- 

 face exposed. 

 Questions: 



1. What is a silo? 



2. What are some of the advantages of a silo? 



3. Name as many different kinds of silos as you can. 



4. What can you say about the proper size of silo to build? 

 Arithmetic: 



1. If a silo costs $332.50 and holds 95 tons of silage, how much 

 does it cost per ton capacity? 



2. A man has 20 cows that will eat 35 lbs. of silage per day each. 

 How many tons of silage will he need to feed these cows 200 days? 



3. If an acre of com produces 9 tons of silage, how many cows 

 will it feed for 200 days, at the rate of 30 lbs. of silage per day? 



FENCINQ 



Kinds of Fences. — Fences of some description are found 

 on nearly every farm. Sometimes these fences are in such 



