ning-surface of the eraser. The beater tions having ball ends are received. Thus universal patented by Mr. Gustav Rasmus, of 239 Winan Street, joints are produced. The side sections are composed has also a lateral reciprocating motion, so that at each Long Island City, N. Y., which is remarkable… … A BLACKBOARD-ERASER CLEANING-MACHINE. ing devices to engage and raise the upper carbon to form the arc. surface of the eraser, tends to force the eraser out The merits of this construction are obvious. Only portions of the guy-ropes being connected at the same from the machine a given distance. The…
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