The first real snow in Park Slope arrives overnight, and by seven the block is a negotiation: stoops, sidewalks, and the corner where the plow left a wall. Brooklyn Snow Angels handles that negotiation — walks shoveled down to clean pavement, steps and entryways opened, salt spread across the shaded stretches where ice likes to linger. Over in the park the Long Meadow is filling with sleds while the crews finish the last address on the list. A cleared path in front of a building is a small kindness done in the cold, repeated door after door. Snow shoveling, clearing and de-icing for Brooklyn.