It may not be amiss to remark, in explanation of the startling and sensational title chosen for this production, that logic has not yet succeeded in framing a title-page which shall clearly indicate the nature of a book. The greatest adepts have frequently taken refuge in some fortuitous word, which has served their purpose better than the best results of their analysis. So it was in the present case. "Danger!" is a thrilling and warning word, suggestive of the locomotive headlight, and especially applicable to the subject matter of the following pages, in which the crimes of a great city are dissected and exposed from the arcanum or confessional of what we may be pardoned for designating the best-known criminal law offices in America.