I've always got an eye out for antique watercolor sets, so lovely and special feeling (and usable still), though they've become so precious they're pretty hard to come by, American sets most of all. This "toy" set with mini paint blocks with was made by Osborne, one of the few 19th century American makers of artists paint, earning renown for especially vivid colors believed by artists to be equal or better to any made in Europe at the time. It dates to the 1860s or 70--previously manufactured by John S Hodgkinson of Philadelphia, Lewis Haehnlen took over manufacturing there in the 1860s, as is specifically called out on the lid of the box. I can find no documentation of this set out there, but it appears to me all of the cakes are original to it, some embossed with the Osborne trade mark, others featuring a star, an eagle, etc.
Box measures 5 1/8" x 2 7/16" x 11/16. Very good antique condition--some light use but some of the blocks look pretty much untouched. The box has clearly seen some watercoloring, and features pencil writing on the side--hard to read but looks perhaps like the same of the shop where the set was purchased plus the name of the owner of the set, and I see NY, too-- all to the good in my opinion, especially in combination with the handmade brushes, which make it easy to imagine them traveling out on plein air painting expeditions.