"I could see it. Just a little light. That's all it was," recalls 71-year-old Harold Churchey. Not a very dramatic statement-until you realize that Churchey is completely blind.

The sudden spark of vision in Churchey's brain was caused by a jolt of electricity coming from the tip of an electrode introduced into his eye minutes earlier by ophthalmologists Eugene de Juan and Mark Humayun. Churchey could not see the men's faces. But if he had, he might have witnessed their masks of professional anxiety give way to twin grins of "Eureka!" After all, the 1992 experiment at Duke University was a landmark in the fast-accelerating quest to give artificial sight to the blind.