A nor'easter usually reaches Somerville in the small hours, and by three in the morning the streets are one unbroken white. That is when Hidden Hollow Acres is already out, headlights on, opening driveways so the first car of the day rolls straight to the road. Plowing, then the walks, then salt down where ice will set — done in the order that gets people out safely. Somerset County snow is heavy wet stuff that often finishes with a rim of freezing rain, and it does not clear itself. There is real pride in a driveway cut clean before anybody is awake to see it happen.