The cleaning sponge can also be used to absorb water and clean soiled matter with a good effect, the length of life is longer, and improves the cleaning effect greatly.

So is the surrounding tissue of her brain, a three-pound (1.4-kilogram), helmet-shaped bolus of fat and protein, wrinkled like a cleaning sponge and with a consistency of curdled milk.

It's tempting to leave your cleaning implement—a damp rag or sponge—hanging around to use the next day, but that could create a germ breeding ground.