Читать книгу Bicycling for Ladies. The Common Sense of Bicycling; with Hints as to the Art of Wheeling—Advice to Beginners—Dress—Care of the Bicycle—Mechanics—Training—Exercise, etc., etc онлайн

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To the many who earnestly wish to be actively at work in the world, the opportunity has come; they need but to come face to face with it to solve this problem of something to conquer, something to achieve.

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The form of the wheel is very ancient, its construction modern, even recent. Its evolution has been gradual. First came the round stick or roller, placed beneath a weight; then a roller with its central portion shaped and thinned to lessen friction; then two disk-shaped sections of a log, connected by a bar upon which they revolved, replaced the clumsy stick.

Each wheel or disk then began to receive separate attention. There was the wear on the edge or rim to be considered, and it was found that if its surface were protected, the disk would last indefinitely longer. Then it was noticed that the hole in the centre of the disk wore unevenly, and it was reinforced, and the hub began to take form. When the rim was strong and the central portion of the wheel remained intact, the disk was found to be heavier and stronger than it need to be to support the outer portion of the wheel. Some of the useless heavy part was removed, and the disk pierced with holes to make it lighter; then these holes were shaped between the remaining portions, which took the form of pillars or spokes. A pillar would break, and be replaced by a rounded stick; and thus, perhaps, the rude idea took form of constructing a wheel out of several pieces, for the sake of securing economy, durability, and lightness.