There is a reader's letter in S. S. Stewart's Banjo and Guitar Journal #93 (Apr./May 1896) from George M. Spence, writing from New York. And a Note [from Samuel Swaim Stewart]: "Mr. Spence [...] was one of our first customers, some seventeen or more years ago, [...] Mr. Spence was at that time in Chicago, where he taught banjo." So, surely Mr. Spence was born before 1860.
