468 REPORT— 1891. 



The braking on the down-grades, to allow the train to 

 descend at the required velocity, is done by using all the four 

 steam-cylinders as air-compressors by reversing the engines, 

 there bemg a special provision of valves for this purpose, simi- 

 lar to the Chatelier arrangement; and, to quote the words of the 

 late well-known American engineer, Mr. W. W. Evans, " this 

 is the most perfect brake imaginable." The wear-and-tear is 

 greatly reduced, as the sliding and rolling of the teeth of the 

 pinions, which in the descent act mainly as the controlling 

 power, work against the smooth, well-greased surface of the 

 rack-rail. The racks and pinions, being, as before remarked, a 

 fixed resistance and fixed power, give absolute control of the 

 train. By this means it can be stopped in its descent at any 

 point, or its motion reversed, on the steepest gradients, re- 

 ducing the risk of accidents to a minimum ; and passengers may 

 travel up and down the steep inclines feeling assured that 

 there is less danger on these sections fitted with the Abt system 

 than on an ordinary gradient. 



This Abt system is employed on the Hartz Mountain rail- 

 way, the rack gradients being 1 in 16'67 ; on the Oertelsbruch 

 and Lehesten line, rack section 1 in 12| ; Oertelsbruch quarry 

 line, 1 in 7'3; on the line from Eisenerz to Vordenburg, in 

 Styria, 1 in 13-3, with an annual traffic of 320,000 tons of 

 heavy goods, besides passengers ; also on the Visp-Zermatt 

 railway, in Switzerland, 1 in 8-33 (this line carries passengers 

 exclusively, and has six diiTerent rack sections) ; the Puerto 

 Cabello and Valencia railway, in Venezuela, incline 1 in 12|-. 

 The Transandine railway, in South America, under construc- 

 tion, will have about eighteen miles of rack upon it, divided 

 into several sections. I have received information by the last 

 English mail that the Japanese Government have decided to 

 use the Abt system for an incline of fiv^ miles in length on the 

 Warin Toge railway, and also that the Neilgherry railway, in 

 India, is to be built with a gradient of 1 in 15. 



The history of the Puerto Cabello- Valencia line is a prac- 

 tical proof of the success of the application of a steep grade in 

 conjunction with low through-grades. The original survey for 

 this line from the seaport to Valencia was laid out as an ordi- 

 nary adhesion railway, and to obtain the required grades the 

 line followed the contour of the hills, gradually rising to the 

 table-land upon which the city is situated. 



The estimates for the adhesion line reached such a figure 

 that it was deemed financially impracticable, and attention 

 was turned to adopting the valley route and the Abt incline. 

 The surveys were made for the new route ; and the difference 

 on the estimated costs was so great that the capital was at 

 once forthcoming, and the line was constructed under the 

 personal supervision of Mr. Carruthers, then the author's part- 



