From the 1874 Plat Map:(Note: You can buy 11" x 17" color copies (which might actually be easier to read) of these and other Lake County townships from the Merrillville-Ross Township Historical Society — the order form can be found here.)
From the 1908 Plat Map:
From the 1926 Plat Book (whoever drew up this plat book was VERY creative in the spelling of people's names):
From the 1939 Plat Book (also some creative name spellings):
- Western Ross Township (includes Merrillville, Lottaville and Turkey Creek)
- Eastern Ross Township (includes southern Hobart, Ainsworth and Deep River)
- Western Hobart Township (includes western Hobart, East Gary and Liverpool)
- Eastern Hobart Township (includes eastern parts of Hobart, East Gary and New Chicago)
- Winfield Township
From the 1950 Plat Book:
- Eastern Ross Township, and extreme southeastern Hobart Township
- Western Ross Township, and extreme southwestern Hobart Township
- Eastern Hobart Township (includes eastern Calumet Township)
- Western Hobart Township (includes most of Calumet Township)
- Winfield Township
From the 1972 Plat Book:
For Porter County plat maps: http://www.inportercounty.org/maps.html.