About three decades ago, when he lived in Dogtown, Richard Kirschman tried to extract water from fog with a box and a fan. It didn’t work, but late last year he came across a method for “harvesting” fog with extremely fine mesh nets, used in places, like parts of Chile, that have lots of fog, but little rain. He thinks it could be used in the Point Reyes National Seashore to harvest water for local…