Morris' build, and the one that I have before referred 

 to 187 as having climbed the Peters Island incline plane. 

 I have no notes as to the grade of that incline, but my 

 impression is that it was i foot in 17. 188 



There was nothing practical in running the loco- 

 motive and tender up this heavy grade, further than 

 demonstrating the traction of plain wheels on the 

 rails, but from it dates an entire change in American 

 practical engineering. 1 " 9 William Milnor Roberts, 

 identified as he was with the system of the Portage 

 road, wrote for the particulars of this performance of 

 the Norris engine, and from them he made elaborate 

 calculations, verifying them by experiments on the 

 Portage inclines. He came to the conclusion that 

 grades up to 100 feet per mile 19 ° could be successfully 

 operated with properly constructed locomotives, and 

 even higher grades by the aid of an auxiliary or help- 

 ing locomotive, and that any of our mountain ranges 

 could and would be crossed without stationary power. 



Mr. Welch, as chief engineer of the Portage, did not 

 agree with Mr. Roberts in this, but in view of the in- 

 creased business, which he foresaw must eventually 

 press on the Portage, he had various plans to increase 

 the capacity of its inclines, his favorite one being 

 simply doubling the tracks and machinery. He was 

 much annoyed by the persistent predictions of his 

 assistant, William Milnor Roberts, that with properly 

 constructed locomotives heavy grades of 100 feet per 

 mile, or even greater, would be successfully overcome, 

 and with the aid of an auxiliary, or helping engine, be 

 found more economical than the inclines with sta- 

 tionary power that had cost the State so much labor 

 and expense; that long before the inclined planes 

 would be taxed to their capacity they would be 



187 In chapter 27, below. 



188 T ne chronology is in error. Norris delivered the William 

 Penn in October 1835; his George H'ashtngton, delivered in July 

 1836, was the one that climbed the incline (Watkins, vol. 1, 

 pp. 129-130, 137a). The grade of the plane was 1 in 15, or 

 nearly 7 percent; that is, a rise of 187 feet in 2,805 feet (W. 

 Hassell Wilson, cited in note 177 above). 



169 Based on a presupposition — imported from England and 

 accepted uncritically by American engineers — that a railway 

 locomotive was not capable of negotiating a grade steeper 

 than about 1 percent, that is, 1 foot in 100. This idea was 

 fixed in George Stephenson's mind by the experiments that he 



superseded by regularly graded roads. We all know 

 these predictions came true, but the change did not 

 take place as soon as Mr. Roberts anticipated, for he 

 at that time thought it would be within ten years, but 

 the planes continued in operation for a period of 

 about twenty years, answering all the purposes for 

 which they were intended, and, what is remarkable 

 and speaks volumes in favor of their construction and 

 careful operation during that time, without a single 

 serious accident. 



After the achievement of the Norris engine in 

 climbing the Peters Island incline there was much 

 correspondence between Mr. Roberts and his friends 

 in Philadelphia. I now regret that I have not pre- 

 served letters to them showing that at that early 

 period he urged utilizing as much as possible of the 

 weight of the locomotive for traction by connecting 

 the wheels. In one of his letters he expressed him- 

 self about in this way: "I, as a civil engineer, make 

 no pretensions to being a mechanical one, but I have 

 satisfied myself that the power evolved in the steam 

 engine is in all cases greater than the traction due to 

 its entire weight, therefore as much as possible of it 

 should be utilized for climbing the heavy grades 

 necessary to overcome our mountain chains." Mr- 

 Henry R. Campbell was one of the correspondents 

 to whom I refer; he took up with great avidity the 

 use of heavier locomotives with a more even distribu- 

 tion of weight on the drivers, and increased traction; 

 two or three years later he obtained a patent for an 

 eight-wheel engine with four connected drivers and 

 four-wheel truck, the type of the standard American 

 passenger engine of the present time . . . . 191 [57] 



and Nicholas Wood made in 1818. A paper by someone on 

 the basis, rise, and fall of this principle is long overdue. Some 

 materials are in Nicholas Wood, Practical Treatise on Rail- 

 Roads (London, 1825; 2d ed., 1838); Thomas Tredgold, Prac- 

 tical Treatise on Rail-Roads and Carriages, 2d ed. (London, 1835); 

 and Samuel Smiles, The Life of George Stephenson, Railway Engi- 

 neer (London, 1857). 



190 Nearly 2 percent. 



191 U.S. patent dated February 5, 1836. This was just before 

 the Patent Office fire of 1836. Restored patent drawing is in 

 U.S. National Archives. 



152 



