Saturday afternoon, I find myself observing raindrops on the car window as children do. Awe and wonder still abound, but I now actively ponder the cohesive properties at work. Each drop lands on the window and glides across the speeding surface, leaving a trail of itself behind. All of a sudden, one fat bulb violently smacks the glass and jolts me from my innocent surveillance. More and more drops splatter forcefully – smack! smack! smack! on the glass like an angry painter splashing heavy streaks of color onto a spotless canvas. The window becomes streaked with paths of tiny, broken droplets. Then comes silence, and once again the raindrops race.