Ebensburg -- Cresson Springs -- The Conemaugh River -- South Fork -- Johnstown -- The Great Flood -- Laurel Ridge -- Packsaddle Narrows -- Chestnut Ridge -- Kiskiminetas River -- Loyalhanna Creek -- Fort Ligonier -- Great Bear Cave -- Hannastown -- General Arthur St. Clair -- Greensburg -- Braddock's Defeat -- Pittsburg, the Iron City -- Monongahela River -- Allegheny River -- Ohio River -- Fort Duquesne -- Fort Pitt -- View from Mount Washington -- Pittsburg Buildings -- Great Factories -- Andrew Carnegie -- George Westinghouse, Jr. -- Allegheny Park and Monument -- Coal and Coke -- Davis Island Dam -- Youghiogheny River -- Connellsville -- Natural Gas -- Murrysville -- Petroleum -- Canonsburg -- Washington -- Petroleum Development -- Kittanning -- Modoc Oil District -- Fort Venango -- Oil City -- Pithole City -- Oil Creek -- Titusville -- Corry -- Decadence of Oil-Fields. THE OLD PIKE. The American aspiration has always been to go westward. In the early history of the Republic the Government gave great attention to the means of reaching the Western frontier, then cut off by what was regarded as the almost insurmountable barrier of the Alleghenies. General Washington was the first to project a chain of internal improvements across the mountains, by the route of the Potomac to Cumberland, then a Maryland frontier fort, and thence by roads to the headwaters of the Ohio. The initial enactment was procured by him from the Virginia Legislature in 1774, for improving the navigation of the Potomac; but the Revolutionary War interfered, and he renewed the movement afterwards in 1784, resulting in the charter of the Chesapeake and Ohio Canal, of which Washington was the first President. Little was done at that early period, however, in building the canal, but the Government constructed the famous "National Road," the first highway over the Allegheny Mountains, from Cumberland in Maryland, mainly through Southwestern Pennsylvania, to Wheeling on the Ohio. This noted highway was finished and used throughout in 1818, and, until the railways crossed the mountains, it was the great route of travel to the West. It was familiarly known as the "Old Pike," and Thomas B. Searight has entertainingly recorded its pleasant memories, for it has now become mainly a relic of the past: "We hear no more of the clanging hoof, And the stage-coach, rattling by; For the steam king rules the travelled world, And the Old Pike's left to die."