A robbery was committed a few days ago on the firm of Robinson & Co., of this city, a report of which appeared in our columns. From information received by the police, a person who had taken a passage on board the "Ariadne," for New York, was suspected, and warrants were issued for his apprehension. The arrest was made, but as the police were bringing the prisoner from the vessel to the quay, a violent struggle ensued. Police-constable Janson was hurled by the prisoner over the edge of the quay into the water, while he, quick as lightning, made a rush to escape. He fled as far as the end of the quay, and was making for the draw-bridge, where he would soon have gained the open road, when his foot caught in a rope, which threw him with fearful violence over the wharf into the pool. In falling, he appears to have come into collision with a boat, and when his body was recovered he was found to be quite dead. The deceased was a young man of powerful build, and had taken his passage under the name of James Williams; but no clue has been obtained at present as to his antecedents. Upon his person was found a bundle of bank-notes, a sovereign, and some silver, and in a side-pocket was a miniature portrait of a young lady, of very beautiful workmanship, set in gold and studded with precious stones. The police are making searching inquiries, and as it is thought that this valuable portrait must have been stolen, it is believed that it will lead to further discoveries. How Howard got through his work at the office that day, he was at a loss to know, for nothing remained on his mind for a moment at a time, except the vague and curious report about the Fatal Chase, and the anticipated visit of the Doctor with further particulars. No sooner had the clock struck six, than he sped away from the office, trusting to his legs to carry him more quickly than the omnibus or car. Before he had time to ask, "Any news of the Doctor?" a well-known voice was heard, and the outstretched hand of his old friend grasped his. "Well, my dear boy, how are you? You see, I need no introductions. Here I am, quite at home in your family circle." "And what news, Doctor Brier?" "A great deal, satisfactory and unsatisfactory. But come and sit down, and I will tell you the whole story." The whole story took a long time to tell, but it may be summed up in a few words.