These excellent topics, doubtless, had their season, and when done, our wholesale dealers in wisdom, the Publishers, well knew that their great patron, the public, would not be content with what had gone before. Something was to be again produced, that would make the press move; and that something, we believe, every one will agree with us, that, notwithstanding the splendour of Genius which the imaginative tribe are endowed with in this mental age, was to be that which was _new_--that, in fact, which would _sell_. This, as might be expected, caused the booksellers and their hacks to look around them, and the tempting gilt which the former held out, (scanty though the quantity always be!) was yet too keen a spur to the flagging wits of hungry scribblers, to allow them to lie idle. Society was once more ransacked, and that which formerly gave pleasure was now found to be too old for entertainment. Bad practices were discovered to exist amongst those with whom honesty was thought to dwell--the seat of justice was found to be but the seat of corruption--and so high in repute had Unions risen in the land, that they even extended to the very pests of society--the men who lived by plunder. It is to this desire for change, then, that we are indebted for those admirable novels of the French writer Paul de Kock, which have lately appeared; and wherein are portrayed, with such faithfulness, the plodding manners and steady characters of shop-keepers, instead of the high-toned conversation of polished society or the homely but innocent simplicities of a country life--that old ground-work of fiction. The same may be said of those "Essays on the Condition of the People,"--"Household Servants,"--the "Old Bailey Experience," and those equally instructive articles on the "Machinery of Crime in England, or the Connection between the Thieves and the Flash Houses," which all owe their origin to the same cause. It therefore can scarcely excite surprise that the Common Lodging House and Cadger should have remained so long without notice, when, if we take but a little time to reflect, we shall easily perceive that this work of observation is but just now going on, and that the very period in which we now live, is what with justice may be called but--the Age of Inquiry.