London, July 17.
Thousands in this great city are quaking with fear of the murderer's knife. Jack the Ripper is back again. The horrible murder committed this morning enables him to cut another notch in the handle of his terrible knife. The details of this morning's crime leaves no doubt that he is the murderer of Alice McKenzie, known to some as Kelly.

He is also guilty of the following crimes:

During Christmas week of 1887 an unknown woman was found murdered near Osborne and Wentworth streets, Whitechapel.

August 7, 1888. Martha Turner was stabbed thirty nine places on the landing of the George Ford (sic) Buildings, Commercial Street, Spitalfields.

August 31. Mrs. Mary Ann Nicholls was murdered and mutilated in Buck's row, Whitechapel.

September 7. Mrs. Annie Chapman was murdered and mutilated in Hanbury Street, Whitechapel.

September 3o. Elizabeth Stride had her throat cut in Berners street, Whitechapel.

September 30. Catherine Eddowes was murdered and mutilated in Mitre square, Aldgate.

November 9. Mara (sic) Jane Kelly was hacked to pieces at No. 26 Dorset street, Spitalfields.

All these murders were audacious, the last extraordinarily so. Police were in front, behind, and all around the assassin when he killed his eighth victim. Before his dreadful work could be completed the tramp of Constable No 272H drove the ghoul away. The constable had left the spot ten minutes before. On his return he found the mutilated body in front of a house wherein two people were retiring. There was a light in the window. He raced down Castle Alley to Castle Street. The only person in sight, Isaac Lewis Jacobs, had a plate in his hand, having been sent for cheese and pickles by his brother. He was arrested, but was evidently innocent. At the sound of the constable's whistle the police came from all directions. The "bull's eyes" threw patches of light everywhere, but no trace of the murderer could be found. The woman was placed in an ambulance. Under her was found a broken clay pipe and a farthing pipe, which may have belonged to the woman or to the murderer.

The body, when taken to the dead house for examination, developed an unusual feature. Jack had done his work with a dull knife. Heretofore the slashes had been clean. Alice McKenzie's body bore marks of Jack's terrible methods, but not of his execution. The clothes were drawn over her head, after the knife had been driven into her neck. A cut four inches long, running towards the groin, had not severed the abdominal wall. On both sides of this cut and along the lateral line below the breast bone were twenty scratches, which would have been slashes with a keen knife.

Every scratch was evidently an attempt to rip. The woman had evidently been taken unawares, as she was strongly built and weighed 140 pounds. She could not have uttered a cry without her being heard by the police. Jack had adopted the , except that in this case his right hand was put over the mouth, the left hand driving the knife into the neck, instead of vice versa.

The murder threw Whitechapel into a condition of fearful excitement. Castle alley was crowded all day with people from all quarters who flocked to the scene. Stories about the crime were on every tongue. At ten o'clock the woman was identified. John McCormack, a porter, said he lived with the woman six years. She was forty years old and was born at Peterborough. Her family lived there until a month ago. They lived in a furnished room in Whitechapel. She did charring work and never got her living on the streets. Sometimes she drank too much. She left the house at four o'clock yesterday afternoon. They had had a tiff. He gave her a shilling and advice not to spend it in drink. She told him she would return to the house at ten last night, and took with her a blind boy, George Dixon, for a walk.

McCormack knew no more. The woman and boy went to the Cambridge Music hall. There they met a man. She asked him to "treat." She then went home and left after saying she was to meet a man at the Cambridge Music Hall. Whether or not she met him ism not known, for the blind boy could by no means identify him except by his voice.

Nothing could more clearly indicate the cunning of the murderer than the selection of the locality - an alley 100 yards long, dark and encumbered by a mass of wagons and barrows, which formerly were stored in a yard in which excavations were going on. There is here a network of streets, courts, and alleys, none of whose residents are likely to go through Castle alley at night, the baths being the only tenanted house on the upper part of it. The others on the left side are small factories and workshops. On the right side is a high board fence shutting off the back yards. A row of small houses faces on Newcastle street. Newcastle street runs parallel with Castle alley, and just below the scene of the murder they are connected by a narrow court. If approached, therefore, from Whitechapel road, the murderer could escape down castle alley into Old Castle street, through the Wentworth street and thence to Commercial street or the lane. If approached from Old Castle street he could escape through castle alley court into the Whitechapel road. This way he did escape.

If hemmed in on both sides, he could still escape through the connecting court to Newcastle street, and thence to Whitechapel road or to Wentworth street, as he chose. There was further cunning and evidence of his intimate knowledge of the locality in the fact that he was just on the boundary line of two police districts. Whitechapel road is patrolled by constables from the Leman street police stations, and no street constables comes from the road down the alley, because that is the district belonging to another division. He must have known that an officer could come toward him only from the bottom of the alley, and his intimate knowledge of the locality and of police rules made his escape as easy as ever. When it is remembered that in all the eight murders committed he has never once been seen by anybody, the fear of him in Whitechapel will be understood, and the superstition in some of the slums that he is invisible does not seem surprising.

The police are absolutely without a clew. Inspector Reid so stated this evening. Jacobs was the only person in the vicinity of Old Castle street. He was imply on an errand, and was released directly. Three other men were arrested on suspicion during the early morning and forenoon, but were almost immediately released upon establishing their identity and their whereabouts at the time of the murder. A search of the lodging houses, which followed close upon the discovery, revealed nothing. Nobody had come in or gone out within the fatal hour who could in any way be connected with the tragedy.

The only hope was the examination of barmen and barmaids along Whitechapel road with reference to the presence of the woman Mackenzie. Prior to the murder there is the possibility, judging from previous cases, that the murderer took her into one of these and got her stupidly drunk before attempting her death. This investigation appears to be the only chance of finding a clew, but it does not appear to have been made. The attempt to surround the scene with a cordon of constables amounted to nothing, as the murderer had passed into Whitechapel road, and it would be quite as easy to hem in wayfarers on that populous avenue as to encircle the population of London. Consequently, the police stand as before, not knowing which way to turn. No doubt they have done and are doing all in their power. Chief Commissioner Munroe and Col. Monsall were on the spot as soon after the murder as telegraphed and horse could bring them. All the detective strength of the metropolitan force have been centred on Whitechapel, and the best brains of Scotland yard not only are but have been at work on the murders up to a month ago. Two constables were nightly on watch in the alley, it being a likely spot for the murderer to select, up to two weeks ago. There was also a night watchman stationed in the alley by a man who owned a number of barrows stored there. The withdrawal of all these left the place free.

There is nothing more for the police to work on at present than there was at the time of the last murder on August 9.