My wife said we should get a birdbath so I found one that has a solar-powered light in its stem. This doesn’t really help the birds, who are mostly asleep by the time it comes on. It’s activated by darkness. The light has a warm, steady, orange glow that doesn’t really illuminate anything beyond itself, but that’s fine. Light pollution is a problem and I’m glad when I go out at night and it’s there, a beacon. It glows all night, which I learned one morning when I had to take a dog out at about five a.m., just before dawn, and even with the sky beginning to lighten the stem was still glowing.
We have a second solar-powered light down by the driveway. It’s very different, though. For one thing it’s motion-activated and only comes on for thirty seconds. But it burns very brightly—so bright, in fact, that if it stayed on continuously I doubt it would last more than an hour or two. But it does its job of providing illumination when we need it.
There’s a metaphor, or maybe a synecdoche—for all I know there could even be a metonym—in that, but I prefer to leave it to others to decide if there’s any significance in it. I don’t want to set one light above the other. They both absorb solar energy and use it at night. And they’re both useful in their own way.
They also remind me of an expression I heard a lot as a kid. When someone called an idea stupid they’d say, “That makes as much sense as a solar-powered flashlight.”
Those people never heard of batteries, apparently.