152 



AMERICAN FORESTRY 



ment of wood in the manu- 

 facture of agricultural im- 

 plements is not controlled by 

 chance. Every use is back- 

 ed by reason. 



Implements drawn by 

 horses are equipped with 

 poles o'r shafts and these are 

 nearly always of wood. This 

 material has first place be- 

 cause it furnishes the neces- 

 sary strength without being 

 too heavy; because it is 

 elastic and will yield with- 

 out jolts and jerks, and such 

 would occur if shafts and 

 poles were of metal. It is 

 necessary, however, if the 

 best results are to be secured, 

 that the wood for shafts and 

 poles be carefully chosen. 

 All woods are not suitable 

 and relatively few are 

 wholly satisfactory. Some 

 lack the necessary resiliency, 

 some are weak and brittle, 

 some are not tough enough 

 to stand the strain. Hickory 

 and ash are more used than 

 any others ; but birch, elm, 

 oak and maple are satisfac- 



A SOWER WENT FORTH TO SOW" 



He continued to go forth in exactly the same way for several thousand 

 years until a better way was discovered, and the better way is illus- 

 trated in the accompanying picture shown below. The teaching here is 

 by contrast the old and the new side by side. Photograph by courtesy 

 of the International Harvester Company, Chicago. 



tory for many kinds of poles, 

 and in some instances the 

 strong yellow pines are ac- 

 ceptable. Most of the shafts 

 which are steamed and bent 

 are hickory or ash. 



Many agricultural imple- 

 ments are equipped with 

 hoppers, chutes, elevators, 

 and conveyors. Most of 

 these belong to machines for 

 threshing, cleaning, sorting, 

 or grinding grain. Platforms 

 provide standing room for 

 the operators. These appli- 

 ances do not require tough 

 woods, but in some instances 

 hard and strong kinds are 

 wanted. Elasticity is not 

 essential, for strains are not 

 usually great, or jolts severe 

 or sudden on hoppers and 

 conveyors. But woods are 

 desired which will take a 

 smooth finish and that are 

 light in weight. Such quali- 

 ties are found in most of the 

 pines, in hemlock, redwood, 

 cottonwood, basswood, tupe- 

 lo, red gum, cypress, and 

 yellow poplar. Boxes, com- 



SOWING GRAIN IN THE NEW WAY 



The machine does better work and a great deal more of it than was possible in the old time when a man threw the grain from his hand, 

 hit or miss, just so it fell somewhere in the field, which it did not always do. Machines distribute it with mathematical accuracy. Photo- 

 graph by courtesy of the International Harvester Company, Chicago. 



