John Peter Salling (or Salley) was among five Virginia explorers who departed March 16, 1742, from a few miles east of Natural Bridge, on a journey to the Mississippi River. The Governor's Council of Virginia had granted a commission for this trip to John Howard for the purpose of reinforcing British claims in the west.

The promised reward of 10,000 acres of land for a successful expedition encouraged Howard's son, Josiah, and Salling, John Poteet, and Charles Sinclair to accompany the elder Howard on the trip. At New River, they constructed a boat covered with buffalo hides and embarked as the first Englishmen to explore that region. They followed the New until the river became too dangerous to navigate, leaving at a major falls and traveling overland to the Coal River, then followed the Kanawha and Ohio rivers, and reached the Mississippi on June 7. The party descended the Mississippi to just below the mouth of the Arkansas River, where, on July 2, they were captured by a large company of Indians, blacks, and Frenchmen. Transported as captives to New Orleans, they were imprisoned as spies, in spite of Howard's claim that they were negotiating peace treaties with the Indians.

After two years' confinement, Salling escaped on October 25, 1744, eventually returning by a southern route to his home in Augusta County, Virginia, in May 1745. Salling's account provided Virginians with their first information about previously unknown regions, including present West Virginia, and he is credited with the discovery of coal on Coal River. In December 1744, Howard was being transported to France when the ship was intercepted by the English. He is known to have reported his adventures after landing in London, but his account has not survived.