I saw Morris step suddenly back from a corner, which he was examining. We all followed his movements with our eyes, for undoubtedly some nervousness was growing on us, and we saw a whole mass of phosphorescence, which twinkled like stars. We all instinctively drew back. The whole place was becoming alive with rats. . . They seemed to swarm over the place all at once, till the lamplight, shining on their moving dark bodies and glittering, baleful eyes, made the place look like a bank of earth set with fireflies. The dogs dashed on, but at the threshold suddenly stopped and snarled, and then, simultaneously lifting their noses, began to howl . . . .
Rats are among the most phobia-inducing animals. For many people, they invoke the “disgust response” typically found in phobias directed at cockroaches and spiders. They are dangerous as vectors of disease and, under certain circumstances, as predators. They've been known to eat people who are injured or trapped in collapsed buildings. Unlike many predators, they don't trouble themselves to kill their prey before beginning the feast.
It’s not surprising, then, that horror stories have made excellent use of rats. As a Christmas treat, I’m presenting some of the best rat tales, by authors like Edgar Allan Poe, Sheridan LeFanu, HP Lovecraft, and George Orwell. Click here to read these Rat Tales. I don't usually post fiction here, but I'm doing so now because it's Christmas time and because the rat has a special place in the lore of the holiday. Seems to me rats must account for a lot of haunted-house stories—they would certainly explain a lot of nocturnal sounds and curtains that move without wind. Christmas was traditionally the time for scary stories in the English-speaking countries, though Halloween has supplanted it in the last century or so.
If you prefer your rat horrors real, check out The Book of Deadly Animals. The rodent chapter is my favorite part of the book.