A route with higher gradients than those adopted on the Juniata throughout this division seems to be called for by the topography of the country.
In his report upon the western division, Mr. Miller gives the following account of the surveys, conducted under his direction by Messrs. Day and Pemberton, his principal assistants: "If a straight line be drawn from Blairsville to Pittsburg, it will be seen that Turtle creek is the only stream that approximates to the proper course of the road, whilst the Loyalhanna, the chief tributary of the Conemaugh, crosses it nearly at right angles, and Spruce Run, Roaring Run, Porter's Run, Beaver Run and others intersect it at various angles of obliquity. Much time and labor were bestowed by Mr. Schlatter and his principal assistant, Mr. Roebling, upon the investigation of this district, and their maps and profiles, loaned to us by the Canal Commissioners, have been of much service in our examinations. From a careful investigation of Mr. Schlatter's preferred route on the ground, it appeared possible to avoid some of the most formidable obstacles which he encountered by adopting a higher gradient than his maximum of 45 feet per mile, and by a reasonable increase of distance at a few points.
"Our trial lines confirmed this, and, in the location made, a maximum of 1. in 100, or 52-8/10 feet per mile, has been used at several places. The cheapness of fuel throughout the whole extent of the western division renders this increase of gradient less objectionable than elsewhere. Bituminous coal, of the best quality, is everywhere abundant, and can be delivered at the depots at from 56 to 84 cents per ton."
The principal changes made in the route referred to in Mr. Schlatter's report Mr. Miller describes as follows:
"Upon the White Thorn our line keeps the left bank, entirely to its mouth, avoiding a tunnel of 600 feet, leading into the valley of Buck Run, and a high bridge over White Thorn creek, and reducing that over the Loyalhanna, from 90 to 50 feet in height. West of Buchanan's summit we run level round the hill, between Porter's Run and Beaver Run, avoiding the Still House summit entirely, where a tunnel of 1,000 feet was proposed, with a cut of 70 feet at its western end, running out to grade in a distance of 1,700 feet.
"Passing Burnt Cabin summit, by a deep cut, the line descends along Turtle creek to the Monongahela.
"Below Murraysville the creek makes a double bend, like the letter S. The former line crossed one of these bends, by a tunnel 600 feet long, whilst ours crosses the other by a short, deep cut, following a remarkable pass by which the hill is nearly cut through. These changes have reduced many of the deep cuts, avoided several bridges, saved three tunnels, and reduced the length of a fourth, amounting in all to a reduction of 2,300 feet of tunneling."
After reaching the Monongahela, two routes present themselves, one following the bank of the stream to Pittsburg, and the other ascending along the slope of the river hills, enters a valley leading by Wilkinsburg and East Liberty. Thence, following this valley, it descends Two Mile Run, and enters the city on the Allegheny side. The latter, though the longest route, and requiring gradients of 50 feet per mile, has been adopted as it presented the only apparently feasible route by which a connection could be formed with a road extending towards the great west.