According to the Merriam-Webster dictionary, satire is "a literary work holding up human vices and follies to ridicule or scorn; trenchant wit, irony, or sarcasm used to expose or discredit vice or folly."
In the poem "A Description of a City Shower" by Jonathan Swift, the poet uses the description of a shower of rain to ridicule the folly, pettiness, hypocrisy, and filth of London. At the time, London was esteemed as one of the world's important cities. Usually when describing rainfall, poets choose beautiful natural settings and evoke the life-giving properties of the rain. In this poem, the rain exposes the awfulness of the city that is usually hidden. The rain creates horrible stinking streams containing such things as excrement, blood, guts, drowned puppies, dead cats, and garbage.
People do anything they can to escape the rain. Women run into shops and pretend to browse, but they don't buy anything. People of opposing political parties temporarily set aside their disagreements and shelter next to each other. According to Swift, the rain makes trembling cowards out of people.
Lines 13 to 16 of the poem develop the poem's satire by creating a vivid negative image of the rainfall. The first two lines describe a cloud rising out of the south. The cloud's color is sable, which is a very dark shade of brown. The word "welkin" means firmament or vault of the sky. Here, Swift envisions a dark storm cloud coming out of the south that covers the sky. Swift then writes that the cloud "swilled more liquor than it could contain." To swill is to guzzle, or drink too much, and it is usually used in reference to alcoholic drinks. So here, Swift is personifying the cloud, comparing it to a drunken person who has consumed too much alcohol. Swift goes on to write that the cloud "like a drunkard, gives it up again." In this expression, Swift is equating the rain with a drunken person's vomit. This adds to the satire; rain is usually depicted as benevolent, but here it is compared to something foul and disgusting.