"Suppose you should wake up Christmas morning and find yourself to be the owner of a bicycle. It is a brandnew wheel and ever ything is in perfect working order. The bearings are well oiled, the nickel is bright and shiny and it is all tuned up and ready for use. If you are a careful, sensible boy you can have fun with it for a long time until finally, like the "One Hoss Shay" in the poem, it wears out and goes to pieces all at once. On the other hand, if you are careless or indifferent or lazy ...