_Pittsburg_, together with _Homestead_, _Carnegie_, _McKeesport_, _Duquesne_, and _Braddock_, is the chief steel-making centre of the Ohio River Valley. There are also large plants at _New Castle_, _Sharon_, _Scranton_, _Johnstown_, _Bellaire_, _Youngstown_, _Mingo Junction_, and _Wheeling_. The steel-plant and rolling-mills at _South Bethlehem_ are designed especially for the manufacture of the heavy ordnance used in the army and navy. Nearly all the cities and towns of Pennsylvania, West Virginia, and eastern Ohio carry on manufacturing enterprises that depend on coal mining and steel manufacture. The great and diversified manufactures of Philadelphia are due to its fortunate situation at tide-water, near the coal-mines. Cheap fuel and water transportation have made it one of the great industrial centres of the world. The anthracite coal of this region is used wholly for fuel and steam-making; it is shipped partly by water from Philadelphia, but mainly in specially constructed cars to the various points of consumption. The soft coal is used also for fuel and steam-making, but a large part of the product is converted into coke and used in the steel-plants. The petroleum of this region is a leading export of the country, the states of western Europe being the chief purchasers. Of agricultural products, hay, dairy products, and tobacco are the only ones of importance. Natural gas is used both as a fuel and in manufactures. The lake-shore centre of steel manufacture depends largely on the low cost of transporting the iron ore, which in part is offset by the increased cost of coal. The low cost of shipping the manufactured product over nearly level trunk lines is a very substantial gain. _South Chicago_, _Toledo_, _Sandusky_, _Lorain_, _Cleveland_, _Ashtabula_, _Conneaut_, _Erie_, and _Buffalo_ are centres of steel manufacture or ore shipment, because they are situated on this great trade-route or line of least resistance. The coal-mines and iron-making plants of the southern Appalachians have a considerable area. The chief manufacturing centres are _Birmingham_, _Richmond_, _Roanoke_, and _Chattanooga_. A considerable part of the Virginia ores find their way to the Ohio River steel-mills. Open-hearth steel is an important manufacture in Birmingham. A large part of the ores smelted in the southern Appalachian region are made into foundry iron. QUESTIONS FOR DISCUSSION What are the advantages and the disadvantages of manufacturing cotton textiles in the New England States? Why have the mining of ore and the manufacture of steel become generally unprofitable in the New England States? What causes have brought about the lowering of the prices of cotton textiles during the past fifty years?--of shoes? What makes the manufacture of artificial ice a precarious business north of the latitude of Philadelphia? What are the advantages and the disadvantages arising from the location of a manufacturing industry at a seaport?