The stories that show the mind of the critic--and the greatest of them come in his later career--are in different fashions riddle-solutions, the most famous being "The Murders in the Rue Morgue," "The Mystery of Marie Roget," "The Gold Bug," and "The Purloined Letter," pioneers in the field of the detective story. In the elaboration of these Poe combined his gift as a narrator with the powers which appeared equally in deciphering codes, discrediting Maelzel's chess player, dealing with the complications of "Three Sundays in a Week," or foreseeing the outcome of "Barnaby Rudge" from the opening chapter. Still, as in the earlier types, they are composed of the things that life is made of, but themselves are uninformed with the breath of life. It has been well said by a recent critic that the detective story is in a way a concession to the moral sense of the reading public, following the paths of the older romance of roguery, but pursuing the wrongdoer to the prison or the gallows instead of sharing in his defiance of the social order. But this concession is one in which Poe had no hand. For him detection is an end in itself; he is like the sportsman who is stirred by the zest of the hunt and shoots to kill, but at the day's end, with fine disregard, hands over his bag to the gamekeeper. It should be said as a last word in the classification of Poe's stories that the best work in the threescore and ten can be found in one fourth of that number, that the remainder are in varying degrees overburdened by exposition, and that the least successful, unredeemed by technical excellence and unanimated by any vital meaning, trail off into "sound and fury, signifying nothing."