 Complete the following phrase:  In 1850, Hudson moved to New York City for his practice, and resided there until his death. He devoted himself to orthopedic surgery and mechanical apparatus for deformities, artificial limbs, etc. During the American Civil War, Hudson was appointed by the U.S. government to fit apparatus to persons suffering special cases of gunshot injuries of bone, resections, ununited fractures, and amputations at the knee- and ankle-joints. He invented several prosthetic and orthopedic appliances to aid in such efforts, and his works received awards at the 