Chinese Grinding Bowl with Wheel

Somewhere, a long boat-shaped tray with a small round dish and a peg handle.

This grinding bowl with wheel is from Hebei Province, China, and dates to the 20th century. It is forged iron. Forged iron bowls and mortars have long been made by village blacksmiths in northern China, where metal vessels were used for grinding herbs, spices and grain. Pictured here, a shallow, elongated vessel in dull brown-grey, pointed at both ends with a gently raised rim. A round concave disc sits near the middle, with a short peg that projects past the edge. The surface is smooth with faint scuffs. It is 34.25 inches wide, 8.75 deep and 13 high.

Part vessel and part puzzle, and not offering a hint.