Both as painter and engraver Hogarth was a deep student of art, on which he has left some commendable writings; but he never succeeded in fulfilling all its conditions. Extravagantly pre-occupied with the philosophical significance with which he purposes to endow his work, he does not always see when he has gone far enough in the exposition of his idea: he darkens it with commentary; he becomes unintelligible by sheer insistence on intelligibility. There are allegories of his in which, still striving after ingenuity, he has piled detail upon detail till the result is confusion worse confounded. But when no excess of analysis has decomposed his primary idea to nothingness, by directing the attention elsewhere, Hogarth strikes home, and compasses most powerful effects. His series of prints, in which are storied the actions of one or more persons--his "Marriage à la Mode," his "Rake's Progress," his "Harlot's Progress," his "Industry and Idleness"--the last a sort of double biography representing the different lives of two apprentices, one of whom becomes Lord Mayor of London, whilst the other dies at Tyburn--all these engraved by himself, partly in etching and partly in line, are, as regards the execution, by no means irreproachable; are frequently, indeed, not even good: but in expression and gesture they are nearly always of startling truth, while the moral meaning, the innermost spirit of every scene, is felt and rendered with the keenest sagacity. At the very time when the genius of Richardson was working a like revolution in literature, Hogarth--and herein lies his chief merit--was introducing domestic drama into art. In England and elsewhere the painter-engraver and the novelist, both creators of the style in which they worked, have had a crowd of imitators; but they cannot be said to have met with rivals anywhere.