GM&O and Illinois Central
(Now Illinois Central Gulf)
Tracks in 2005.
The Civil War destroyed the M&O, more than once, as each side rebuilt it when they gained control. After the Civil War they built additional segments in the south. But the segment that interests me is that they finished building to Cairo on May 1, 1882. In 1886 they bought the St. Louis and Cairo and converted it to standard gauge to complete a connection from Mobile to East St. Louis except for ferry service at Cairo. So in my 1928 RR Atlas, the route from Mobile to East St. Louis was M&O. r2parks has a 1935 timetable map. If you right-click the map and save it as a file, you can then use a file viewer to obtain a resolution that is good enough to read the city names.
In 1892 the Illinois Central built a steel truss bridge across the Ohio and the M&O used this bridge to cross the river. It was replaced during 1949-52 with a modern truss bridge using many of the same piers.
Southern Railway gained control in 1901, but relinquished it in 1940 when the M&O assets were merged with the Gulf Mobile & Northern to from the Gulf, Mobile & Ohio. The GM&N was essentially a parallel route in Mississippi. Remember, in the 1800s when one had to use horses to get to the depot, 15 miles between railroads allowed both railroads to be viable. But after cars, trucks and paved roads were developed, two railroads separated by just 15 miles became redundant.
In 1939 GM&O tried to acquire the Alton Railroad but that effort failed in the ICC hearings. In 1945 they negotiated with the bond holders of the Alton, paid $1,190,925.85 to the B&O even though the B&O's claims were $15,000,000, and agreed to split traffic with the IC, Wabash, and Chicago & Eastern Illinois. The 1945 merger proposal to the ICC of the GM&O and Alton railroads was successful. [acmeme written by James H. Lemly] A "corporate tree" indicates the Alton RR merged with the GM&O on 5-31-1947.
Update: a 1949 photo album of 85 photos