1851 Great Exhibition: Official Catalogue: Class V.: Gustavus Edward Beckers
503. BECKERS, GUSTAVUS EDWARD, Paddington.
Self-acting railway siding stop.
The object of this contrivance is to prevent accidents on railways caused by carriages or trucks getting accidentally out of sidings, and thereby occasioning collisions with passing trains. Any carriage or truck can be pushed into a siding, but cannot come out again without being purposely removed.
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