electromagnetism
"Light is a product of electromagnetism- essentially electromagnetism is like a pebble dropping in a lake, and light is the wave that travels out from it."
"Electromagnetism is, like gravity, a fundamental force of nature. You may find gravity obvious; you feel it every day. It is what keeps you grounded. Electromagnetism, however, is slightly harder to wrap your head around; charge is less intuitive than mass! You are not surprised when an apple falls from a tree, but when a beam of water is bent in the presence of a glass rod, there is a more magical mood to it."
"For a quickie off-the-cuff about the wave model I usually start telling people to put luminescent ping-pong balls in a swimming pool and turn out the lights ... you see the balls bobbing about: electromagnetism is like that, the balls are kinda like charges, only there's no water."
METAMIA is a free database of analogy and metaphor. Anyone can contribute or search. The subject matter can be anything. Science is popular, but poetry is encouraged. The goal is to integrate our fluid muses with the stark literalism of a relational database. Metamia is like a girdle for your muses, a cognitive girdle.