I
- Improvised ingenuity: a waterworks carried on one man's signature — and the class's named-gap limb Famous Stories & the Record
- Incorporation: the election of 1866 Government
- The Indiana State Library: the Indiana Collection and its digital arms Sources
- The industrial buildings as architecture: the elevator, the steel plants, and the absent brewery Architecture
- The industrial clusters, beat by beat: mill and elevator, steel, data and battery The Story of New Carlisle
- The industrial fortunes, by sector Wealth
- Industrial Revolution Section
- Industry-Defining Inventions — The Plants Finish and Generate; They Do Not, on This Record, Invent Inventors & Inventions
- Influencers & Digital Creators Section
- The Institute's music: one printed line of musical instruction, and no catalogue found Arts
- Institutional origin oddities: the $1,500 schoolhouse, the library that moved out of its monument, the museum in a café Famous Stories & the Record
- The intermediate-goods trade: selling the means of the next farm Industrial Revolution
- The interurban pair and the crossing war of 1907 The Story of New Carlisle
- Inventors & Inventions Section
- Investigators and organizations: the local record UFO Sightings