Bit of an obscure question – has anyone heard of a “toushi”?

I'm doing some research for a book on Okinawan/Ryukyu history and I'm trying to track down pictures or records of a device known as a "toushi". Apparently this was a mill or grinder of some sort, Chinese in origin, and "toushi" was the local name for it. Google returns nothing when I look it up, so I'm wondering if anyone on here has heard of anything along these lines.