A Chalk Line Depot

My driving wheels slowed right at the brink of the porch step. A dizzying drop... straight down to the garden path! I reversed three careful inches, scanning along the edge for a safer route. There, resting beside an iron railing post, lay a chunky stub of blue sidewalk chalk, rounded from past play. I nudged it with my cowcatcher. It rolled along the gritty concrete with a dry scrape, leaving a thick, powdery cerulean line trailing directly behind it. It looked just like a fresh rail line laid out on the stone! I nudged it twice more, extending the blue stripe safely parallel to the ledge.