Rust
the yellowish coat of peroxide which forms on the surface of iron exposed to moist atmosphere. To prevent the rusting of iron utensils, oil, paint, varnish, plumbago, grease, or any substance which will protect the metal from the moist air, may be employed. In all ordinary circumstances iron decomposes water, abstracts the oxygen, and combines with it, thus forming rust. RUSTCHUK In botany, a disease of plants, which shows itself on the stems and leaves of many plants, and on the ears of grasses, both of the cereal grasses and of many pasture and forage grasses, in brown, yellow, or orange colored spots, and after destroying the epidermis of the plant assumes the form of a powder which soils the fingers when touched.