CHAPTER XII. 



THE USES OF WOOD. 



Wood Serves so Many Purposes and enters so largely 

 into human activities that it may be said to be the most 

 useful of all natural products, excepting only food. Iron 

 is looked upon as -the most useful of metals. Wood is 

 not a metal, but in its usefulness it may be placed above 

 iron, which it is replacing in many cases where the latter 

 formerly was exclusively used. Iron and wood have dis- 

 placed and replaced each other in public favor time and time 

 again, so that their respective claims to supremacy have not 

 yet been decided. For instance, in the manufacture of 

 bicycles, wood rims were first used, and then gave way to 

 iron and steel on account of their lighter appearance and 

 strength. Now, with better methods of construction, wood 

 is again in use, and giving general satisfaction. However, 

 each has its place, and the two often work to better advan- 

 tage in combination. Experiments have shown that in 

 tensile strength hickory exceeds iron and steel of the same 

 length and weight, and hickory and long-leaf pine resist 

 greater endwise compression than wrought iron. The elas- 

 ticity of wood enables it to yield to greater stress than 

 metals without receiving permanent distortion, and in like 

 manner it will resist high temperatures without warping, 

 holding its shape until consumed or broken down by mere 

 weight. 



In Comparison with Iron, Wood is lighter, easier to 

 work and handle, at present cheaper, and in many cases 



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