Introducing himself to his readers at the close of the eighteenth century, Dr Colquhoun wrote: "Police in this country may be considered as a new science." A full generation later, or to be more precise, in the year of Queen Victoria's accession, one of the leading magazines of the day found occasion to remark as follows: "The art of preventing offences is unbeaten ground--has hardly had a scientific teacher. On laws and general legislation, on the theory of crimes and punishments, on prison discipline, on the execution of offenders, and all the ulterior proceedings of delinquency, we have treatises without number; but on the institutions of police we have not a single work, except perhaps the matter-of-fact publication of the late Dr Colquhoun."[1] Since this paragraph was first printed a period of unparalleled literary activity has been witnessed, a period so prolific of book-making that the thirty-nine miles of shelves with which the main building of the British Museum is furnished have not sufficed to contain the ever-increasing accumulation of volumes that must be housed. It is true that in modern melodrama the detective has been found an almost indispensable property, nor has he been altogether neglected by the modern novelist; there are scores of blue-books containing evidence collected by Parliamentary Committees on the subject of police, and there is no lack of excellent manuals wherein the constable's duty is defined and explained; but at the dawn of the twentieth century, and in spite of the over-crowded state of our public libraries, we are still waiting for the advent of the teacher who will investigate and expound for us the police sciences. In the following pages some attempt will be made to approach this strangely neglected subject, not indeed by the avenue that a scientist would use, but simply to trace in outline the story of English police, keeping in view the underlying principles that have directed, as well as those political and other considerations that have controlled, its evolution. Previous neglect is not however the only reason why the institution of police calls for historical treatment. On three other grounds in particular can the subject claim recognition; it deserves notice on account of its interest, on account of its antiquity, and on account of its importance.