603 (1917) (obligation to furnish passenger support on a branch line previously devoted solely to carrying freight) Lake Erie & W.R.R. 262 (1910) (obligation to operate a common passenger educate in its place of a mixed passenger and freight train) Chesapeake & Ohio Ry. 209 Chesapeake & Ohio Ry. 208 Chesapeake & Ohio Ry. Public Comm’n, 267 U.S. So. Ry. v. Clough, 242 U.S. Public Serv. Comm’n, 242 U.S.