Electro Magnets Clear Tacks Off Universal City Streets (Mar, 1930)
Or you could just sweep the streets…
Electro Magnets Clear Tacks Off Universal City Streets
ELECTRO magnets on a bar mounted on wheels and trailed after a car make the streets of Universal City, California, safe for motorists. The magnets pick up nails, tacks, pieces of wire, lost bolts and nuts and a wide variety of other metal objects which if left in the streets would cause punctures and other tire trouble. Frank Graves, electrical chief of the city, invented the puncture fighter.