Credit: Courtesy of the Library Company of Philadelphia
In 1786 David Rittenhouse commissioned master builder Joseph Ogilby to build him a house at the corner of 7th and Mulberry (Arch) streets, in which he erected an observatory and used a telescope of his own design to continue his celestial observations. In 1790 Congress appointed Rittenhouse first Director of the U.S. Mint, which operated from a building erected in 1792 just down the block from his home.
