DelawareOnline, there is a nice little video piece focusing on the Brandywine Springs Amusement Park. You can find the video here. The two men featured in the video, Mark Lawlor and Mike Ciosek, are without a doubt the two foremost experts on the park and its history. Lawlor is the author of the book Brandywine Springs Amusement Park: Echoes of the Past 1886-1923, which is the only comprehensive work on the history of the park (and an invaluable resource). In the early 1990's, spurred on by his research, Lawlor co-founded the Friends of Brandywine Springs with Mike Ciosek, who has served as its president for nearly 20 years. (Mike has also served, among other things, as the lead in all the archaeological digs at the park, and certainly knows more about how it was built than anyone else alive.)
I happen to know a good deal about the park myself, so if you have any questions about anything mentioned in the video (which can also be found after the jump), or about any of the wonderful pictures used, feel free to ask. Other than that, enjoy!