Thus, floating down our black highway, sullenly frowned upon by the knitted brows of Blackfriars, Southwark, and London, each in his lowering turn, I was shown by my friend Pea that there are, in the Thames Police Force, whose district extends from Battersea to Barking Creek, ninety-eight men, eight duty boats, and two supervision boats; and that these go about so silently, and lie in wait in such dark places, and so seem to be nowhere, and so may be anywhere, that they have gradually become a police of prevention, keeping the river almost clear of any great crimes, even while the increased vigilance on shore has made it much harder than of yore to live by ‘thieving’ in the streets. And as to the various kinds of water-thieves, said my friend Pea, there were the Tier-rangers, who silently dropped alongside the tiers of shipping in the Pool, by night, and who, going to the companion-head, listened for two snores—snore number one, the skipper’s; snore number two, the mate’s—mates and skippers always snoring great guns, and being dead sure to be hard at it if they had turned in and were asleep. Hearing the double fire, down went the Rangers into the skippers’ cabins; groped for the skippers’ inexpressibles, which it was the custom of those gentlemen to shake off, watch, money, braces, boots, and all together, on the floor; and therewith made off as silently as might be. Then there were the Lumpers, or labourers employed to unload vessels. They wore loose canvas jackets with a broad hem in the bottom, turned inside, so as to form a large circular pocket in which they could conceal, like clowns in pantomimes, packages of surprising sizes. A great deal of property was stolen in this manner (Pea confided to me) from steamers; first, because steamers carry a larger number of small packages than other ships; next, because of the extreme rapidity with which they are obliged to be unladen for their return voyages. The Lumpers dispose of their booty easily to marine store dealers, and the only remedy to be suggested is that marine store shops should be licensed, and thus brought under the eye of the police as rigidly as public-houses. Lumpers also smuggle goods ashore for the crews of vessels. The smuggling of tobacco is so considerable, that it is well worth the while of the sellers of smuggled tobacco to use hydraulic presses, to squeeze a single pound into a package small enough to be contained in an ordinary pocket. Next, said my friend Pea, there were the Truckers—less thieves than smugglers, whose business it was to land more considerable parcels of goods than the Lumpers could manage. They sometimes sold articles of grocery and so forth, to the crews, in order to cloak their real calling, and get aboard without suspicion. Many of them had boats of their own, and made money. Besides these, there were the Dredgermen, who, under pretence of dredging up coals and such like from the bottom of the river, hung about barges and other