The police were working yesterday upon two crimes among the city's Italian residents, one of which was the work of the so-called Black Hand. The latter crime was the wrecking by means of a bomb of the glass frontage of the double tenement at 164 and 166 Elizabeth Street early yesterday morning. The other was the murder of Tomaso Ciancrimino on Saturday afternoon before a crowded butcher's store between Second and Third Avenues in 107th Street.

The Elizabeth Street tenement is in the midst of an Italian settlement, and is on the block between Spring and Broome Streets. Upon the ground floor opening from the street are a saloon and a small grocery store, both the property of Michael Angelo Alonge, who, with his wife and four girls, the oldest of whom is 10 years, lives in the rear of the first floor.

About 2:30 in the morning Policeman George F. Bruckner was in the block on Elizabeth Street immediately above the tenement. He knew that Policeman George Kingston was around the corner in Broome Street.

Bruckner got to the corner of Spring Street and Elizabeth when he saw some sparks sputtering up from the doorstep of the grocery story in the tenement 164 and 166 Elizabeth. He noted that in front of the store on the sidewalk was a box filled with coal belonging to a small dealer in the vicinity. Thinking that this concealed the source of the flame, he ran toward the sparks, at the same time whistling for Kingston. At his signal Kingston came around the corner.

"What's up?" he demanded.

"Fire in the tenement," returned Bruckner, stopping for the moment. Kingston looked up at the windows. "I don't see any fire," he said. "Why, there, down on the sidewalk," said Bruckner, impatiently.

Then Kingston saw the sputtering, but not until the two had hesitated long enough to save their lives.

Now they hurried toward the doorstep. When they were still fifteen or twenty feet away there came a sharp detonation that threw them to the ground. The large glass windows of the grocery fell into small fragments within the store, while the stock was hurled from shelf and counter. The front of the liquor store also was blown in sections inward. As high up as the fourth story the tenement shattered down its windows. From the upper windows of four houses across the street glass fell. The iron doorstep before the grocery store, where the bomb had lain, showed a hole six inches in diameter.

For a moment after the explosion there was complete silence in the neighborhood, while the two policemen lay where they had fallen. At the end of that still moment a child's cry sounded in one of the tenements. As though that had been the signal, a babel of sounds ensued. The voices of men, women and children were united. Then from the houses of the neighborhood into the shivering air rushed the inhabitants of the quarter. The policemen, unhurt, got up and went to the first man, they saw.

"What is it?" they asked. "Black Hand," he said and then remained silent.

Meanwhile the Sergeant in the Mulberry Street Station, who had felt the shock had hurried his detectives to the spot. They, with the two policemen, asked for the proprietor of the saloon and grocery store. Alonge, who didn't seem inclined to say much, was put forward as the man. After a time he seemed to have more confidence. Then he told the police that he had received a number of letters from the Black Hand demanding money, in which the threat had appeared that unless the money was paid his place would be blown up. The first letter came on Dec. 8. It had been mailed at Station S, on Broadway near Howard Street. Six letters had been received, the last on Jan. 9. All were signed "Mano Nero," and were adorned with daggers and a coffin pierced with a dagger. Six hundred dollars had been demanded as the price of Alonge's life.

"Get on a subway train," the letters reiterated, " and ride to Fort George. Come at 5 o'clock in the morning and come alone. I will ask you for a match and then give me the money. Look out, for if you don't come with the money we will blow up the house. We will kill you. Don't go to the station house."

Alonge hadn't paid any attention to the letters, as he thought, they were idle threats intended merely to frighten him. He said that he had been in the country twelve years and was a native of Sicily. He declared that he hadn't an enemy here or in Italy.

The two policemen said that they hadn't seen any one passing in the street for some time before the explosion, and that no one was in the vicinity of the house at the time they first noticed the sparks, evidently the burning of a fuse. No trace of any parts of a bomb or cartridge were found.

Ciancrimino, who was murdered in Harlem, was a prosperous Italian contractor who lived with his wife and daughters at 326 East 106th Street. So far as his family knew, he had not received any threatening letters. After luncheon on Saturday he left the house on business. Two policemen were on Second Avenue, near 107th Street, when they heard the sounds of two revolver shots. They hurried to 107th Street, and in front of No. 237 found the contractor lying on the pavement with a wound through his left eye. At his feet lay a 44-calibre revolver, with its six chambers loaded. A number of people had been walking through the street at the time of the shooting, more were in the butcher's shop, and children were playing in the street before it, but no one questioned by the police had seen the shooter or shooters.

Detective Sergft. Petrosino and his men, who are working on both cases, believe that the murderer of Ciancrimino is Antonio Gallo of 2091 Second Avenue. Galio, who owed Ciancrimino $300, disappeared shortly after the murder. From relatives and friends of the dead man the police learned that Ciancrimino had made an appointment to meet Gallo on 107th Street Saturday afternoon to get his money. A shoemaker who lives in the same house as Gallo said, Gallo entered his shop a few minutes after the murder and asked what had happened. The shoemaker told him that he thought a man had been shot.

In the face of this statement of the shoemaker the wife of Gallo told Capt. Corcoran that her husband had been in his house all Saturday afternoon, and that after the murder a man shouted up to him that his friend had been shot around the corner. She was unable to tell why her husband had disappeared.