Complex sentence: The park grew out of the Lemon Hill estate of Henry Pratt, whose land was originally owned by Robert Morris, the signer of the Declaraction of Independence and was dedicated to the public by City Council's ordinance on September 15,1855.
Split into simpler sentences: The park grew out of the Lemon Hill estate of Henry Pratt, whose land was originally owned by Robert Morris, signer of the Declaration of Independence. It was dedicated to the public by City Council's ordinance on September 15,1855.