DEVELOPMENT OF THE AMERICAN KAIL AND TRACK. 



685 



Figs. 72-75. 

 Pennsylvania Railroad Standard Rails, 1875, 1880, 1887, 1890. 



(From ilrnwings inthe U. S. National Museum.) 



Figs. 70 79. 

 Standard Chicago, Burlington and Quincy Railroad Company's Standard Rails 



18C-, 1880, L885, L890. 



Prom chart I CI U 



