At four in the morning in February, Riverside Avenue is one blue streetlight after another and nothing is moving but the plows. Gardner Contracting & Excavation, Inc. is out in that hour clearing Burlington driveways and lots — plowing, pushing back the ridge the city plow leaves across the end of a drive, shoveling walks, and salting and sanding where ice sets up overnight. Squalls cross Champlain without much warning, and eighty inches over a winter is an ordinary total in this town. The measure of the night is simple: the drive is open before anyone needs it. Headlights back out onto bare pavement, and that is the whole job.