I know for certain the NY State Legislature established on 15 April 1817 the "New York Institution for the Instruction of the Deaf and Dumb" (its proper registered name)in New York City.
My great-grandfather (afflicted from dyptheria) graduated from it in 1864. I found information about the school in a book covering about NY City's history from 1600's to early 1900's. I found the book at a used book store in 1972 and donated it to the Archives of the State Of Florida after I published my family history in 1984.
Since this is so close to NJ perhaps your relative attended the same school.