The Central News, telegraphing this morning, says:--shortly before closing time this morning three men in the Black Swan public house, Hanbury-street--George Lucas, James Miller, and Thomas Pearman,--being struck by the demeanor of a stranger who was present, submitted him to interrogation, and finally to a search. The three men assert that they took from him a large clasp knife, and that with the assistance of a constable they conveyed him to Commercial-street police station, where two more knives, four rings, some hairpins, and some money were found upon him. After inquiries had been made, however, the man was liberated

The streets in the vicinity of the recent tragedies are still patrolled by police and detectives in augmented numbers, and the closest surveillance is maintained on suspected localities. Yesterday morning at an early hour, the police being informed by some Italians at Eyre-street Hill that a man who answered the description of the murderer had been seen there, and that he had been seen in the company of a woman, who hastily left him, Detective Sergeant John Robinson, of the G Division, having borrowed a cloak and hat, went in search of the man, who was said to have entered a cabyard in Phoenix Place, Clerkenwill, and hid himself behind some cabs. Some Italians soon afterwards entered the yard to see if the officer was successful in capturing the man. Some men employed in the yard went to the officer, and wanted to know what he wanted there, and on being told that he was a police-officer they left, but directly afterwards two other men went to him, and demanded that he should clear out at once, for they were going to protect their master's property. Robinson informed them that was a police-officer, and requested them to keep quiet. One of them then struck him a violent blow, after which he took from his pocket a knife with which he stabbed the officer in the face, whilst the other man kicked him. The officer calling out that he had been stabbed, a young man whom he knew came into the yard and was also stabbed and assaulted. The Italians, who were there afterwards, went to the policeman's assistance, and some other police officers having arrived, the two men were at once taken to the King's Cross Road Police Station and there charged. The prisoners, whose names are James Philips and William Jarvis, were afterwards taken before the magistrate at the Clerkenwell Police Court and remanded.

Sir Charles Warren witnessed a private trial of bloodhounds in Hyde Park yesterday morning, two famous stud hounds, Barnaby and Burgho, belonging to Mr. Brough, of Scarborough, being employed. Six runs were made, Sir Charles himself twice acting as the hunted man. The trail was sometimes crossed and the dogs were temporarily checked, but on the whole, considering the coldness of the scent, the experiments could not be considered altogether disappointing. The Chief Commissioner appeared pleased with the result of the trials.