San Francisco Chronicle: It may not have had as much cachet as scaling an Antarctic peak to make a point, but hundreds of people knelt or crouched in unison across from San Francisco’s Ferry Building on Saturday to urge dramatic action against global warming. Their bodies formed the number 350 – the ambitious rallying cry for a global network of environmentalists. The San Francisco event was one of more than 5,200 coordinated demonstrations across 181 countries organized by 350.org, which draws its …