Neuerungen an Maschinen zum Graviren, Schneiden und Ciseliren von Metallen und zum Schneiden von Holz, Stein und anderer Materialien
My invention consists of a couple of tool-stocks, each carrying an engraving, chasing, or other tool in a hollow revolving mandrel, and made to reciprocate, at the same time alternately with each other, three or four times with each revolution for making engraved or chased ground-work on gold or plated jewellery, silver, silver-plated, or washed ware ...