Hi David,

Thanks for your response. I did see those listings of "Sydenham" in the database but not finding any attributed to Clementson Brothers prompted my inquiry. Basically, I'm trying to figure out if they continued the pattern past J Clementson's ending operation date of 1865 for archaeological dating purposes. Also, the name "Sydenham" has been used by a number of other manufacturers:
Anthony Shaw in 1856 to describe a white granite shape/molded pattern, Francis Morley & Co (1845 to 1858) for a floral tranferprint pattern, Belleek of Ireland in the 1880s for a woven basket, and Burgess & Leigh registered a pattern in 1905, among others.

Tim