[Dog-stealing, we are more particularly informed by Col. Hawker, is reduced to a perfect system in London, and carried on by a set of fellows who, by their cunning and peculiar knack, are enabled to avoid all detection in their nefarious traffic, and thus, by extortion of rewards or sales of stolen dogs, reap a rich harvest for the whole fraternity from the well-stored pockets of the numerous dog-fanciers of the English capital. The villains engaged in this business are known among themselves under the too often abused sobriquet of "the Fancy," and assuming the garb of different mechanics, prowl about the streets, oftentimes with the proper tools in their hands, carelessly watching the movements of every dog that passes by, ready to grab him up the first fitting opportunity. The dog is then concealed till a suitable reward is offered for him, when, through the intervention of a third person, a trusty agent of the society, he is delivered over to his rightful owner, the actual rogue never appearing in the whole transaction. If no reward, or an insufficient one, is offered for the recovery of the dog, he is either sent off to the country, or, perhaps, cautiously exposed for sale in some distant quarter of the city, or perhaps killed for his skin alone. These gentry, however, prefer returning dogs to their owners for a moderate compensation, as they thus know at what rate the animal is valued, and cherish the hope of soon being able to steal him again, and thus obtaining another reward. There have been instances of a lady paying, in successive rewards, a sum not less than fifteen guineas for a miserable little lap-dog not worth as many shillings. If anything is said about the law, or threats of prosecution held out in the notice offering a reward for a "lost or stolen dog," the death of the kidnapped animal is inevitable, as the "Fancy" prefer sacrificing an occasional prize rather than run the risk of detection by some enthusiastic or stubborn dog owner. These fellows, as well as thieves generally, are said to have a method of quieting the fiercest watch-dogs by throwing them a narcotic ball, which they call "puddening the animal." The following account, extracted from Hawker's work, will give the American reader a 'perfect' insight into the maneuvering of these sharpers.