John "Jack" J. O'Brien (1932-) worked as both a railroad clerk and yardmaster for more than forty-four years. O'Brien started his career with the Pennsylvania Reading Seashore Line (PRSL) in the early 1950s. Eventually, the PRSL became part of Conrail, the railroad from which he ultimately retired. This small collection documents policies and procedures for railroad employees at the Pennsylvania-Reading Seashore Line (PRSL), Pennsylvania Railroad (PRR), Penn Central, and Conrail.