This book needs no preface. The preface is too often used as a literary hold-all—that nondescript addition to the legitimate impedimenta of a journey, into which are stowed away all sorts of things which should have found room in the portmanteaus. It ought, however, to be strictly limited to matter personal to the author, or needed as a preliminary explanation of his “argument.” But no one who will be at the pains to peruse these pages need have any doubt as to their purpose and aim, and the writer's anonymity ousts the personal element altogether.