The Wagner Free Institute of Science is the oldest U.S institution that offers free public education to adults. It was founded by William Wagner, a wealthy merchant who worked for the banker and philanthropist Stephen Girard. Traveling around the world on business trips, Wagner accumulated an impressive collection of scientific specimens over time. Retiring at a young age, he opened the doors of his Elm Grove estate just outside of Philadelphia to people for free lectures and discussions on a variety of subjects. Wagner incorporated the Institute of Science in 1855. In 1865, the library and museum received its own structure, which was designed by famous John McArthur, Jr. The Insitute remains at the same location to this day. Wagner led the institution until his death in 1885, and was succeeded by the influential paleontologist Joseph Leidy.