As stated, canal-boats could traverse this course as early as 1834, and the uninformed must wonder how a canal-boat could vault the towering crest lying between Hollidaysburg and Johnstown, which the Pennsylvania Railway crosses with difficulty at Gallitzin, more than two thousand feet above sea-level. The answer to this introduces us to the Alleghany Portage Railway, a splendid piece of early engineering, which deserves mention in any sketch of early deeds of expansion and promotion in America. The feat was accomplished by means of inclined planes; the idea was not at all new, but, under the circumstances, it was wholly an experiment. The plan was to build a railway which could contain eleven sections with heavy grades, and between them ten inclined planes. A canal-boat having been run into a submerged car in the basin on either side of the mountain, it could be drawn over the level by horses or locomotives, and sent over the summit, 1,441 feet above Hollidaysburg, on the inclines by means of stationary engines. The scheme was first advanced early in the history of the canal, but it was not finally adopted until 1831, and in three years the portage railway was opened for traffic. The ten planes averaged about 2,000 feet in length and about 200 feet in elevation. They were numbered from west to east. Certain of the levels were quite long, that between Planes No. 1 and No. 2 being thirteen miles in length; the total length of the road was thirty-six miles. It was built through the primeval forests, and an aisle of one hundred and twenty feet in width (twice as wide as that made for the Erie Canal) was cleared, so that the structure would not be in danger of the falling trees which were continually blocking early highways and demolishing pioneer bridges. Two names should be remembered in connection with this momentous work,--Sylvester Welch and Moncure Robinson, the chief and the consulting engineer who erected it.