584 



Popular Science Monthly 



A farmer built a record silo tower and 



now finds that a windmill on top catches 



every breeze that blows 



A Silo and Windmill Tower in One 



SILOS have been built by the thou- 

 sands within the last few years, but 

 few farmers have made use of the com- 

 liination shown in the illustration. This 

 is a two hundred-ton silo of hollow-tile 

 Ijlock construction wdiich supports the 

 farm's windmill tower. The photograph 

 shows how the silo is filled with green 

 corn in the autumn. 



The silo walls, five inches thick, are 

 made of hollow clay blocks, with each 

 mortar joint re-enforced by a heavy wire. 

 The door-frame is of concrete re-en- 

 forced with vertical rods, to which the 

 wall-re-enforcing is tied. The roof is of 

 concrete and metal lath, thus making the 

 entire structure fire-proof, and wind- 

 proof. Dead-air spaces make the walls 

 impervious to moisture and reduce the 

 loss from freezing to a minimum. 



It is now a common practice among 



farmers to buy a twelve or f ourteen-inch 

 cutter co-operatively and to use it on 

 five or six jobs in a season in filling si- 

 los. Such outfits have a capacity of from 

 eight to ten tons per hour. One corn- 

 binder is required in the field to keep 

 the crew busy. Two men are employed 

 in the field loading the cut corn bundles, 

 and from three to five teams are needed 

 to haul the corn to the cutting machine 

 at the silo. This method has proved to 

 be the most generally practised through- 

 out the corn-belt states. 



A Magnetic Machine Which Saves 

 Waste Iron 



IN order to separate the tiny grains 

 of ore from the lumps of gravel and 

 sand, after the final washing process, 

 thereby saving iron that would ordinari- 

 ly go to waste, a magnetic ore machine 

 has been developed which may substan- 

 tially increase the income of mining 

 properties. 



The sand, gravel and finely divided 

 iron particles are washed through a long 

 trough beneath which a series of power- 

 ful electromagnets are situated. As 

 the liquified mass slowly flows forward, 

 the iron grains are drawn to the bottom 

 of the trough and retained, because of 

 the power of the magnets, against the 

 floor of the containing walls. 



Iron in the water is caught on the magnetized 



walls of the sluice-box, with a saving of many 



hundreds of dollars 



