In 1716 appeared his "Trivia, or the Art of Walking the Streets of London", a poem in three books, for which he acknowledged having received several hints from Swift. It contains graphic and humorous descriptions of the London of that period. It depicts the city with photographic accuracy, but also acts as a guide to the upper-class and upper-middle-class walkers of society. By taking a mock-heroic form, Gay's poem was able to poke fun at the notion of complete reformation of street civility while also proposing an idea of reform in terms of the attitude towards walking. In January 1717 he produced a comedy, "Three Hours After Marriage", which was thought to be grossly indecent (without being amusing) and a failure. He had assistance from Pope and John Arbuthnot, but they allowed it to be assumed that Gay was the sole author.