Simplify the following text for a Grade 9 native English-speaking person.
Original: The Finke River was named by John McDouall Stuart in 1860 after an Adelaide man , William Finke , who was one of the promoters of his expedition .
Simplified: The Finke River was named by John McDouall Stuart in 1860 after William Finke , an Adelaide man , who was one of the people who paid part of the cost of his expeditions .