But now there's only one craftsman left standing who makes it: Eisaku Kawase, 89, works out of Iida, Nagano Prefecture, and is carrying on a tradition passed down to him by his father and grandfather.

IIDA, Nagano Prefecture—Hideo Shimizu has been frustrated by the reluctance of a peace memorial museum here to display panels about the infamous Unit 731, where he worked during World War II.