Nautical readers will observe that I have taken the liberty (for obvious reasons connected with the law of libel) of planting a screw-pile lighthouse on the Girdler Sand in place of the light-vessel. I mention the matter to forestall criticism and save readers the trouble of writing to point out the error. R. A. F. Gravesend CONTENTS I THE CASE OF OSCAR BRODSKI I The Mechanism of Crime II The Mechanism of Detection II A CASE OF PREMEDITATION I The Elimination of Mr. Pratt II Rival Sleuth-Hounds III THE ECHO OF A MUTINY I Death on the Girdler II “The Singing Bone” IV A WASTREL’S ROMANCE I The Spinsters’ Guest II Munera Pulveris V THE OLD LAG I The Changed Immutable II The Ship of the Desert THE CASE OF OSCAR BRODSKI PART I THE MECHANISM OF CRIME A surprising amount of nonsense has been talked about conscience. On the one hand remorse (or the “again-bite,” as certain scholars of ultra-Teutonic leanings would prefer to call it); on the other hand “an easy conscience”: these have been accepted as the determining factors of happiness or the reverse. Of course there is an element of truth in the “easy conscience” view, but it begs the whole question. A particularly hardy conscience may be quite easy under the most unfavourable conditions--conditions in which the more feeble conscience might be severely afflicted with the “again-bite.” And, then, it seems to be the fact that some fortunate persons have no conscience at all; a negative gift that raises them above the mental vicissitudes of the common herd of humanity. Now, Silas Hickler was a case in point. No one, looking into his cheerful, round face, beaming with benevolence and wreathed in perpetual smiles, would have imagined him to be a criminal. Least of all, his worthy, high-church house keeper, who was a witness to his unvarying amiability, who constantly heard him carolling light-heartedly about the house and noted his appreciative zest at meal-times. Yet it is a fact that Silas earned his modest, though comfortable, income by the gentle art of burglary. A precarious trade and risky withal, yet not so very hazardous if pursued with judgment and moderation. And Silas was eminently a man of judgment. He worked invariably alone. He kept his own counsel. No confederate had he to turn King’s Evidence at a pinch; no one he knew would bounce off in a fit of temper to Scotland Yard. Nor was he greedy and thriftless, as most criminals are. His “scoops” were few and far between, carefully planned, secretly executed, and the proceeds judiciously invested in “weekly property.”