Galvanized Iron

Iron coated with zinc to protect it from rusting; it is cleaned with dilute sulphuric acid and dipped in melted zinc; mainly used for thin plates, wire, and water IMG:content-0211.jpg:[graphic][graphic][merged small] can be made more easily to a middle tube. The boiler is moreover made with special provisions that it shall not be strained by unequal expansion of its parts. The vertical or inclined water tubes form a very efficient heating surface.