‘The most beautiful base ball game in the history of the league’

Aug. 17, 1882, Providence Grays 1, Detroit Wolverines 0, in 18 innings.

http://sabr.org/gamesproj/game/august-17-1882-radbourn-slugger

The box score is at the end of the story. The 18-inning game took 2 hours and 40 minutes to play.