The following are the different kinds of wrought iron most generally known in this country.
Best Yorkshire Iron - produced by certain well-known firms of long standing (see p. 299). This iron can be more thoroughly relied upon for strength, toughness, and uniformity than any other made in this country. It is generally specified for important work intended to withstand an unusual stress, or to resist sudden shocks, or changes of temperature.
Other Yorkshire manufactures - Staffordshire Iron, Scotch Iron, Cleveland Iron, Newcastle Iron, Middlesborough Iron, Welsh Iron, etc. etc., are other descriptions of bar and plate iron in the market. They vary considerably in quality; some of them possess considerable strength and toughness, are only half the cost of best Yorkshire iron, and are more generally used for ordinary purposes.
These different varieties are generally distinguished by marks or brands, which are described at p. 296. The qualities of the different kinds of iron are further referred to in connection with the brands under which they are sold.
Wrought Iron is prepared for the market in several convenient forms.
Ordinary Dimensions are those generally made and kept in stock. Everything required of different dimensions from these must be paid for at a higher price. The ordinary dimensions for each district are given in the list of extras, p. 291.
The extras charged in South Staffordshire, also in the North of England, Wales, and Scotland, are shown in the list at page 291, which is copied from that compiled by Messrs. Boiling and Lowe, London.
Dead Lengths and Exact Dimensions are also charged for extra, that is when a bar must be the exact length specified within 1/2 inch, or when a plate must be a special unusual length by a special unusual width in disproportion.
Iron of irregular or unusual figure or dimensions, or cut according to sketches, is also charged extra.
Bar Iron includes simple sections - round, square, or flat.
Ordinary dimensions are generally from 1/2 inch to 3 inches diameter, or sides, increasing by 1/16 of an inch each size.
If under 1/2 an inch diameter, they are classed as rods; or if under 3/16 inch diameter, as wire.
Flat Bars. - The ordinary dimensions are generally from 1 foot by 1/4 of an inch to 6 inches by 1 inch, the width increasing 1/8 of an inch and the thickness increasing 1/16 of an inch (at the same time) in the various sizes.
Bars of these sections may be readily obtained of to 22 feet in length without extra charge.
Half round, Oval, Convex, Half-oval, Hexagon, Octagon, and Tyre iron, are other sections which are useful for different purposes, but which need not be more fully described.
Bar iron is classified as to quality in the manner described at p. 274.
Best Yorkshire Bar Iron is used for locomotives, and in superior shipbuilding, also for bolts and fastenings of very important structures.
Best Best Bar Iron of other descriptions is used for all very important work where the expense of Lowmoor, Bowling, or other best Yorkshire irons excludes their use.
Best Staffordshire Bar Iron is used for ordinary work in bridges and roofs.
Common Bar Iron is used where the iron requires hardly any forging, and is not expected to offer much resistance. It suffices for hurdles, standards, and, in fact, ordinary work.