The Parisian flâneur is a figure made famous in the last century by the writings of Walter Benjamin, but can also be said to be related to the 19th century English idler as well as to figures in German literature, art and cultural theory. Heinrich Heine's flâneur first appears with that name in articles written by Heine in Paris in December 1841 that were published in Heine's Lutezia of 1854. These articles followed the publication in Paris in May 1841 of Louis Huart's Physiologie du flaneur - a work which has been cited in studies of the Parisian flâneur, but which, like Albert Smith's even less well known Natural History of the Idler upon Town of 1848 (a work based on a series of Punch articles of 1842 entitled the "Physiology of the London Idler"), has not recently been republished or described in full. To redress this situation, Huart's Physiologie du flaneur of 1841 and Smith's Natural History of the Idler upon Town of 1848 are introduced and reproduced here in unabridged form together with the illustrations of John Leech to Smith's 1842 articles. Smith (like Leech) was a friend of Dickens and Huart's work provides background information for the work of Heine, Baudelaire, Benjamin, and Hessel amongst other chroniclers of the modern metropolis. In addition to providing contemporary analyses of the 19th century flâneur, the 'panoramic' physiologies of Huart and Smith are important examples of 19th century caricature, parody and satire.