clearing snow

The guy that plows our walkways does it at 1:30am. It only takes about 20-30 minutes, but I can't figure out why he does it at such odd hours. The machine he uses is like a riding lawn mower except that it has a plow on the front. Maybe he's like my dad and he's so excited he can't wait. Last night he was really noisy. Usually I just hear the scrape, but I never see him. Last night I actually saw him. He was speeding that thing back and forth. There were a lot of crashing sounds at one point. He was out of sight, but it sounded as though he was hitting a lot of items. The funny part is that it was still snowing as he cleared the walkway...