It was my original intention when I contracted with my publishers for these sketches from my diary, to avoid such narratives as hinged upon matters of love between the sexes, and especially to avoid all those matters of abduction of females for unholy purposes, the detection and exposure of the schemes of procuresses, or the rescuing from a life of infamy girls of respectable parentage and home surroundings, from both the country and city--matters which frequently come into the hands of detectives, and with which old detectives, in particular, are painfully conversant. I could fill a quarto volume with what has come under my own eye of that nature, with recitals far more romantic in their truthfulness than are the cunning devices of the most imaginative novelists. Indeed, the more astute novelists of the sensation school are wise enough to gather instruction, and obtain from interviews with detectives the plots which they work up, out of facts given them by these officers. In my own experience I have been, indeed (at one time especially, when it seemed to me as if all the scribblers had gone mad upon sensation tales), harassed and vexed by what we would now term "interviews," fishing from me the issues of this or that experience. It was my purpose, to which I shall adhere, of course, to give publicity to not a line in these narratives which may not properly fall under the eye of the most fastidious or the most innocent child. Nevertheless, such is the course of life the detective is obliged to lead, finding himself frequently among the vilest characters,--thieves, gamblers, highway robbers, unfortunate and lost women, and wretches too low and vile to be named here, even by the crimes or base offences which they commit,--that it is almost impossible to give the full history of anything, with all the incidents of a nature interesting (in some respects) which may have attended it. The scenes which occur in New York, for example, in one day, if gathered into a book, such as the regular police force and the detectives might furnish, would astound the uninitiated; and were they recited in all their details, would, many of them, horrify and disgust, as well as "astound," the reader. At this writing there are crowding upon my memory many occurrences in my life, that I have been called to take a part in, which would hardly be fit for these pages, in view of the extreme immorality that generated them, or follows in their trail, which yet have their romantic side. Most of these affairs, to which I now especially refer, relate to the life of fallen women, their first enticements from the path of virtue, their utter ruin, or their final rescue. But it were better that the public remain ignorant of these things as far forth as possible, than to be well informed. Yet the eye of sympathy cannot but fill with tears of pity over the ruined and wronged; and as I write, I feel a strong impulse to go aside from my original intention in these tales, and