rare original and largely intact late 19th century reverse-painted glass advertising sign for senour's floor paint. the chicago-based senour mfg. company, founded in the 1870s, frequently advertised themselves as being the "pioneers of pure paints."the single-sided plate glass sign retains traces of paint from three of the original paint samples and outer edges of the fanciful gilded lettering (likely flaked off over time). the sign was fabricated by the zero marx sign works, which was owned by eccentric millionaire zero marx, who owned a subdivision on the north side of chicago known as "zero park." courtesy of the bldg. 51 archive.