Here's a scan of a Maine Central Railroad schedule from 1931. The Maine Central Wikipedia entry details the "retraction" of the railroad after World War I.
Following World War I, Maine Central began retracting. It sold or abandoned lines such as the narrow gauge logging systems, as well as its ferries and steamships. In the 1930s it began to change its locomotives from steam powered to diesel powered.
Faced with increased competition from cars, trucks and buses, Maine Central operated its last passenger train on September 5, 1960, and continued to reduce its freight business to reflect changing traffic.The Maine Central doesn't yet appear on this 1860 map of New England railroads, but shows up on the 1899 version.