Gagger
A turned piece of rod iron for binding the surface sand firmly to the cope. If the surface below the joint extends but a little way, a three-inch turn at one end is sufficient; the long end resting against the bar is pressed firmly thereto by the rammed sand, and the sand below the bars is sustained by this means; but if the lift is deep, the other end of the gagger must be turned at right angles also, one inch being enough in this case, the object being to hang the gagger on the flask-bar, at the same time allowing it to rest upon a slight thickness of soft sand at the bottom. By this means it becomes impossible for the hanging sand to pull the gagger out. The former is termed a plain, and the latter a hooked gagger. See BAR; FLASKS. Galvanized Iron is made by coating clean iron with melted zinc. The iron is first subjected to a thorough cleansing in pickle containing 1 per cent of sulphuric acid, after which it is scoured well in clean water and then dipped in a bath of melted zinc, the surface of which is covered with salammoniac in order to dissolve the oxide which gathers on the surface of the molten zinc. The best quality is made by first depositing a thin film of tin upon the iron by galvanic action. See ZINC-COATING; TINNING; PICKLE.