What do the firemen do for fun every night in Fahrenheit 451?

In Fahrenheit 451, when the firemen are bored, "they set the ticking combinations of the olfactory system of the Hound." The Hound "lives" in a kennel in the firehouse. It has eight legs and neon lights for eyes that flicker on. It makes a humming sound that Montag compares to a "great bee." In addition to the humming, the Hound also growls. Montag describes the sound as a "combination of electrical sizzle, a frying sound, a scraping of metal, a turning of cogs that seemed rusty and ancient with suspicion."
The firemen allow the mechanical beast to hunt small animals such as cats, rats, or chickens that they turn loose. Bets are taken to see which animal is captured first by the Hound. When the Hound catches its prey, it injects the target with a sedative. The firemen then dispose of the animal by throwing it in the incinerator.