Galvanized iron by its zinc surface is protected from corrosion by the weather, though the protection is not very efficient in the presence of acid or sulphurous fumes, and accordingly it is extensively employed for roofing, especially in the form of corrugated sheets.
The ground about the hut was made solid and protected from corrosion by a palisade of wattled osiers, thus creating the earliest form of the fondamenta, or quay, which runs along the side of so many Venetian canals and is so prominent a feature in the construction of the city.
When carbonic acid is present the dissolved oxide is soon precipitated as basic carbonate, so that the corrosion of the lead becomes continuous.
Hoisting ropes are weakened by deterioration and breakage of the wires, due to corrosion and repeated bending.
To prevent corrosion the rope should be treated at intervals with hot lubricant.
The surface of vessels may be spangled with gold or platinum by rolling the hot glass on metallic leaf, or iridescent, by the deposition of metallic tin, or by the corrosion caused by the chemical action of acid fumes.
Exposure to air and rain also causes slight corrosion, but to nothing like the same extent as occurs with iron, copper or brass.
As the percentage of aluminium rises, and all strongly resisting corrosion in air or sea-water.
(2) The carburizing incidentally carburizes the brickwork of the furnace, and thus protects it against corrosion by the molten slag.
It is still in great demand for certain normal purposes for which either great ease in welding or resistance to corrosion by rusting is of great importance; for purposes requiring special forms of extreme ductility which are not so confidently expected in steel; for miscellaneous needs of many users, some ignorant, some very conservative; and for remelting in the crucible processAll the best cutlery and tool steel is made either by the crucible process or in electric furnaces, and indeed all for which any considerable excellence is claimed is supposed to be so made, though often incorrectly.
In steam boilers artificial galvanic couples are often set up by the suspension of zinc plates in the boiler, so that the corrosion of the zinc may preserve the steel boiler plates from waste.
In 1872 he suggested the use of caustic lime to prevent the corrosion of iron ships by the bilge water, which he noticed was acid, and in 1878 he began a determination of the velocity of white and coloured light by a modification of H.
In the same year the admiralty consulted the Royal Society as to a means of preserving the copper sheathing of ships from corrosion and keeping it smooth, and he suggested that the copper would be preserved if it were rendered negatively electrical, as would be done by fixing "protectors" of zinc to the sheeting.
It is a disadvantage of the system that defects of proportion, material, or workmanship, which would be of less moment in an old-fashioned construction, may become an element of danger in building with the steel cage, while the possibility of securing a permanent protection of all parts of the cage from corrosion is a most serious consideration.
It is agreed that the first step in the preservation of metal-work against deterioration or corrosion is the obtaining of absolute cleanness of metal before the application of paint or oil.
The following are the requirements of the New York building law in regard to the protection of iron or steelwork against corrosion, &c.: " All structural metal-work shall be cleaned of all scale, dirt and rust, and be thoroughly coated with one coat of paint.
The basal plane, so common on calcite and many other rhombohedral minerals, is of the greatest rarity in quartz, and when present only appears as a small rough face formed by the corrosion of the crystal.
Two thousand summers have imparted to the monuments of Grecian literature, as to her marbles, only a maturer golden and autumnal tint, for they have carried their own serene and celestial atmosphere into all lands to protect them against the corrosion of time.