240 IRRIGATION FARMING. 



low, so that the wheel is below the ridge of barns or tops 

 of trees near by. This not only prevents the mill from 

 receiving full force of the wind, but subjects it to vary- 

 ing currents that tend to toss the mill about from one 

 point to another and prevent it from doing the work 

 properly and in strong winds the effect is sometimes 

 damaging. It is better economy to erect a mill too high 

 than too low, as frequently the upper current of air is 

 moving sufficiently to run a mill while it would not run 

 in the lower current. Again, the upper current is more 

 steady at all times, and will run a mill at more uniform 

 speed, with less strain, and with greater satisfaction to 

 all concerned a little extra material for the tower in the 

 start should not be taken into consideration if it is to 

 effect the workings and safety of the mill for years to 

 come. The most important point of a windmill tower 

 is the anchorage. Probably the best way is to dig holes 

 four feet deep and fill them with stone laid in water 

 lime or cement ; in this is embedded, to serve as an 

 anchorage, a two-inch bar of iron with one end flattened 

 and holes punched in for the tower bolts. If it is not 

 convenient, posts may be used with pieces spiked across 

 the bottom for anchors ; this is the method generally 

 employed. Wooden towers should be well painted every 

 five years. It is not well to enclose a tower with siding. 

 It offers a greater grasp for the wind and adds but little 

 strength. It is well, however, to enclose the lower sec- 

 tions to form a pump house. This adds greatly to the 

 strength and appearance. 



Such is the popularity of the steel wheel that where- 

 ever it has been introduced it has driven the wooden 

 wheel out of the field. The modern steel tower stands 

 straight, stiff and supreme. It is twice as strong, weighs 

 only one-third as much, and presents less than one-sixth 

 the surface of a wooden tower to the sweep of a storm. 

 It will not decay, and when galvanized is proof against 



