If his fatherʼs pupils made too much noise in the house, Frederic had only to place himself at the piano to produce instant and perfect quiet. One day when Professor Chopin was out there was a frightful scene. Barcinski, the master present, was at his witsʼ end, when Frederic, happily, entered the room.[6] Without deliberation he requested the roisterers to sit down, called in those who were making a noise outside, and promised to improvise an interesting story on the piano, if they would be quite quiet. All were instantly as still as [Sidenote: CHILDREN SPELL-BOUND BY HIS PLAYING.] death, and Frederic sat down to the instrument and extinguished the lights.[7] He described how robbers approached a house, mounted by ladders to the windows, but were frightened away by a noise within. Without delay they fled on the wings of the wind into a deep, dark wood, where they fell asleep under the starry sky. He played more and more softly, as if trying to lull children to rest, till he found that his hearers had actually fallen asleep. The young artist noiselessly crept out of the room, to his parents and sisters, and asked them to follow him with a light. When the family had amused themselves with the various postures of the sleepers, Frederic sat down again to the piano, and struck a thrilling chord, at which they all sprang up in a fright. A hearty laugh was the _finale_ of this musical joke. Further on in his life we meet with a companion picture to this story, which affords us an excellent example of Fredericʼs talent for improvisation, profound knowledge of counterpoint, and mastery over all technical difficulties. Like all gifted and accomplished musicians, he showed an especial preference for the organ as offering wide scope for the freest improvisation. It was customary for the students of the Warsaw University to assemble about eleven in the morning for service at the Wizytek Church, at which artists and _dilettanti_ performed vocal masses with and without orchestral accompaniments.