His son, Charles, took over in 1874, moving the business a short distance to 19th St.  2040 I St. is not owned by George Washington University, the only structure on the block which is under different ownership.
In 1874, Charles took over his father's business and moved it near 19th St. 2040 I St. is not under George Washington University's ownership; this is the sole building on the block that has a different owner.