The memorial, designed by sculptor Augustus Saint-Gaudens, consists of a bronze tablet featuring a relief of Maxwell, a local philanthropist and park commissioner, affixed to a boulder.

Maxwell was also a prolific philanthropist, donating to numerous educational endeavors in the city, including the Long Island College Hospital and the Brooklyn Institute of Arts and Science.

[3] A committee was formed to raise money for this purpose, with Charles A. Schieren as its chairman,[4] and they commissioned noted American sculptor Augustus Saint-Gaudens to create a memorial plaque.

Due to persistent vandalism of the monument, the plaque was removed by the New York City Department of Parks and Recreation in the early 1970s.

It remained in storage until 1997 when, thanks to support from the David Schwartz Foundation, the plaque was repaired and loaned to the Brooklyn Museum of Art.

Two replicas of the original plaque were made, with one re-affixed to the boulder and the other on display at the Saint-Gaudens National Historical Park in Cornish, New Hampshire.

Near the bottom of the plaque, the following is inscribed: "THIS MEMORIAL ERECTED BY HIS / FRIENDS IS THEIR TRIBUTE TO HIS / DEVOTION TO PUBLIC EDUCATION AND / CHARITY IN THE CITY OF BROOKLYN".