Slow Accumulation

Every time you step outside in your everyday shoes, tiny particles of dirt find their way inside. These bits—sand grains, soil flecks, small bits of grit—slip past the edges with each footfall. Day a…

Each time a car passes over a gravel-strewn road surface, a few tiny rocks settle into the tire treads. These particles, smaller than a pea, wedge into the rubber grooves that channel water and provi…