146 TRANSACTIONS OF THE [FEB. 1, 



without either the first or second forms of permanent set in the 

 track ; the rails appearing to the eye to have a smooth surface 

 when not under tlie trains. I have designated such rails as the 

 fourth form, representing the best condition of track, for they are 

 in perfect service to the eye. For the trackmen's special benefit 

 they will hereafter be designated as the fourth or proper form. 



The undulations which remain in the tracks for the figures 

 given are individually so minute, that at present they cannot be 

 further reduced by the skilled trackmen. To reduce the undu- 

 lations in the track to the low limits mentioned, it has been 

 necessary to do a great deal of work which may be briefly sum- 

 marized as follows : 



First. To investigate the nature of the irregular undulations, 

 and their causes. 



Second, To provide rails with broad heads, which will dis- 

 tribute the wheel pressure to more metal for wear and side sta- 

 bility, and at the same time to have stiffer sections as girders in 

 order to distribute the wheel loads to more ties and to greater 

 area of ballast and roadbed. 



Third, To distribute the metal in the sections so that the re- 

 quirements of the second statement would be met, and at the 

 same time to design sections that could be easily rolled, and that 

 would permit of the introduction of a grade of steel of 50 per 

 cent, higher elastic limits than the older rails, and that would 

 still be hard, tough and not brittle. 



Fourth, To go to the mills and carry out methods of manu- 

 facture suitable for the heavier sections as to composition, hot- 

 bed treatment, and smoother finish under the straightening 

 presses. 



Fifth. To produce sections in which the final results would be 

 better and more economical than those they replaced. 



By the lantern slides and other diagrams I shall be able to 

 show you that the limited undulations already stated for the sec- 

 tions have been realized on man}' hundred miles of track and that 

 in the past fifteen years — principally the past eight — the undula- 

 tions in many tracks have been reduced to one-third of their 

 former amount. 



During the same period, to meet the demands of service, the 

 static wheel loads of the motive power and rolling stock have 

 been increased. The freight car wheel loads have been trebled 

 during this time. 



I need hardly say to you that by reducing the undulations in 

 the track to one-third of their amount fifteen years ago, the 

 dynamic eflfects from the wheel loads have been reduced in 

 a greater ratio, so that the combined static and dynamic effects 



