The essay of Charles Baudelaire, entitled Le Peintre de la Vie Moderne, to be found in Volume III of his collected works (L’Art Romantique), remains thus far the standard reference study concerning Guys, though deficient in biographical details.  Other critical studies are by Camille Mauclair, Roger Marx, Richard Muther, and George Grappe; and recently Elizabeth Luther Cary in a too short but admirably succinct article characterised the Guys method in this fashion:  “He defined his forms sharply and delicately, and used within his bounding line the subtlest variation of light and shade.  His workmanship everywhere is of the most elusive character, and he is a master of the art of reticence.”  Miss Cary further speaks of his “gentle gusto of line in motion, which lately has captivated us in the paintings of the Spaniard Sorolla, and long ago gave Botticelli and Carlo Crivelli the particular distinction they had in common.”  Mauclair mentions “the most animated water-colour drawings of Guys, his curious vision of nervous elegance and expressive skill,” and names it the impressionism of 1845, while Dr. Muther christened him the Verlaine of the crayon because, like Verlaine, he spent his life between the almshouse and a hospital, so said the German critic.  Furthermore, Muther believes it was no mere chance that made of Baudelaire his admirer; in both the decadent predominated—­which is getting the cart before the horse.  Rops, too, is recalled by Guys, who depicted the gay grisette of the faubourgs as well as the nocturnal pierreuse of the fortifications.  “Guys exercised on Gavarni an influence which brought into being his Invalides du sentiment, his Lorettes vielles, and his Fourberies de femmes.”

It is not quite fair to compare Guys with Rops, or indeed with either Gavarni or Daumier.  These were the giants of French illustration at that epoch.  Guys was more the skirmisher, the sharpshooter, the reporter of the moment, than a creative master of his art.  The street or the battle-field was his atelier; speed and grace and fidelity his chief claims to fame.  He never practised his art within the walls of academies; the material he so vividly dealt with was the stuff of life.  The very absence of school in his illustrations is their chief charm; a man of genius this, self-taught, and a dangerous precedent for fumblers or those of less executive ability.  From the huge mass of his work being unearthed from year to year he may be said to have lived crayon in hand.  He is the first of a long line of newspaper illustrators.  His profession was soldiering, and legend has it that he accompanied Byron to Missolonghi.  The official career of his father enabled the youth to see much of the world—­Greece, the Balkans, Turkey, Persia, and perhaps India.  On returning to France he became an officer of dragoons and for some time led the life of a dandy and man about town.  With his memory, of which extraordinary tales are told, he must have stored up countless films of impressions, all of which were utilised years later.