Poor's Manual of Railroads was an annual railroad publishing from 1868 to 1924.

They are close to two thousand pages of teeny, tiny type and tables in a book about 5-1/2" wide and 8-1/2" high, up to 4" thick. 

Major financial institutions and suppliers took ads in the book. 

This is the same Poor that we know as Standard and Poor's today. 

The book often included maps of the states, showing railroad lines. Here is the map for Wisconsin and Michigan from the 1903 edition.

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