Walter Thomas Spencer was a second-hand bookseller and art dealer, based at 27 New Oxford Street, London.
He wrote an autobiography and Notable personalities. An illustrated who's who of professional and business men and women, 1925.
Around 1910 he acquired a lot of canvases that were in poor condition, some of which went on the market as by Whistler, and some possibly by Walter Greaves. Some were sold to Messrs Dowdeswell, and were shown to E.R. and J. Pennell, who were dubious about the authenticity of many works.
Kelly's London Post office Directory, London, 1893; Pennell, Elizabeth Robins, and Joseph Pennell, The Whistler Journal, Philadelphia, 1921 , pp. 125-136; Spencer, Walter T., Forty years in my bookshop, London, 1925; Ancestry.co, uk website.