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ONE:An interesting example in the use of belts for communicating power to movable machinery is furnished by the travelling cranes of Mr Ramsbottom, in the shops of the L. & N. W. Railway, at Crewe, England, where powerful travelling cranes receive both the lifting and traversing power by means of a cotton rope not more than three-fourths of an inch in diameter, which moves at a high velocity, the motion being reduced by means of tangent wheels and gearing to attain the force required in lifting heavy loads. Observing the operation of this machinery, a person not familiar with the relations between force and motion will be astonished at the effect produced by the small rope which communicates power to the machinery.