Edo-kiriko craftsman Shuseki Suda does not blink while engraving intricate lines on the surface of glassware. Sometimes he can even keep his eyes open as long as five minutes.
"If I close my eyes, even if it is less than a second, I might miss the line I'm cutting. You can never erase a line once you make it," he says.
Kiriko, or Japanese cut glass, originated in the Edo Period. It was influenced by English cut glass brought to Japan by Portuguese trading ships. The first kiriko was believed to have been made by glass craftsman Kagaya Kyubei, in 1834. His kiriko immediately became popular among Edo citizens, and over 60 items -- including tableware, medicine bottles and ornaments -- were reportedly made.