“The Reds this time went first to the bat, and Wright and Barnes each got in scratch hits, and on errors of Coons and Craver three runs were made, Craver giving O’Rourke first by a muff.” The Times (Philadelphia), September 6, 1875, p4
Previous earliest use (Dickson Baseball Dictionary, 3rd edition, 2009):
1ST USE. 1879. “[A ball that falls between several fielders] would generally be considered a base-hit, providing none of the players touched the ball, although it would be of the kind known as a ‘scratch hit’” (Chicago Tribune, July 20; Peter Morris).