Central Railroad of New Jersey
My 1968 reprint of an 1868 Travellers Railway Guide, shows through "Palace Sleeping Cars" operating via CNJ between New York (Elizabeth), Pittsburgh and Chicago. In fact, this was the fastest route between New York and Chicago at the time, as close as I can tell, 48 hours and 20 minutes! ...
From: Joel Rosenbaum
Subject: Allentown route discontinuance
... The Allentown route to Chicago ended on June 30, 1873.
[from the R&LHS Newsgroup.]