I just like these old 15 games, with blocks that one is meant to mix up then slide around to get back in numerical order. Simple and slow and tactile. This one with handwritten number in graphite--looks perhaps as if written over at some point, I presume because the earlier ones had worn pretty well away. Funnily, the extra block, or plug--which must be removed in order to play--is numbered 18 rather than 16, suggesting perhaps a misread of the original number, and lack of logic in figuring it out! I like moments like that.  Walnut I believe, with nice finger joints at the corners of the tray the carved tiles sit in.

3 1/2" x 3 1/2" x 1/2". Very good antique condition. Walnut I believe. One small nick to the surface of the wood at one corner, as documented--minor and really only visible if looking for it.