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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The rear wheel revolves very rapidly, in the process becoming virtually a gyroscope; and a gyroscope will maintain the plane in which it revolves unless other forces intervene. The front wheel takes its motion from the friction of the surface over which it is propelled, and after the bicycle is in motion, the forces that are applied to control and direct its movement are friction and resistance. After the cyclist is mounted, there is the added complication of a constantly shifting centre of gravity, caused by change of balance. The steering is effected by changing the direction of the front wheel, the rear wheel being enabled to follow by a slight slipping over the wheeling surface. If the change of direction is too abrupt, the rear wheel will slip enough to lose its hold on the surface, and the weight of the rider will be suddenly shifted from above the point of support (the axle of the rear wheel) to the top of the rim of the wheel, thus becoming a lever with the weight on the end of the long arm, and the bicycle falls over.