- Fort Stevens was an American military installation that guarded the mouth of the Columbia River in the state of Oregon. Built near the end of the American Civil War, it was named for Civil War general and former Washington Territory governor Isaac I. Stevens. The fort was an active military reservation from 1863–1947. It is now listed on the National Register of Historic Places.
- Infinitesimal (Wikipedia)
In mathematics, an infinitesimal number is a non-zero quantity that is closer to 0 than any non-zero real number is. The word infinitesimal comes from a 17th-century Modern Latin coinage infinitesimus, which originally referred to the “infinity-eth” item in a sequence.