d it, sort of like seeing the vapor trail high in the sky of a plane that is itself not visible. Interestingly, when the experimentalists who built Gargamelle met in 1968 to discuss their plans for neutrino experiments, the idea of search- ing for neutral currents wasn't even mentioned—an indication of how

ced in its path that could record the few events in which neutrinos might interact with the detector material. A huge new detector was built, named Gargamelle after the giant- ess mother of Gargantua, from the work of the French writer Rabelais. This five-meter-by-two-meter "bubble chamber" vessel was fill

ng board, tested the detector using a proton beam directly, and took a great deal more data. At a conference almost a year later, in June 2974, the Gargamelle collaboration presented overwhelming confirmation of the signal. Meanwhile the competing collaboration had found the cause of its error and confirm