From www.mutopiaproject.org

Étude Op. 10, No. 1 in C major, known as the Waterfall étude, is a study for solo piano composed by Frédéric Chopin in 1829. It was first published in 1833 in France, Germany, and England as the first piece of his Études Op. 10. This study in reach and arpeggios focuses on stretching the fingers of the right hand. The American music critic James Huneker (1857–1921) compared the "hypnotic charm" that these "dizzy acclivities and descents exercise for eye as well as ear" to the frightening staircases in Giovanni Battista Piranesi's prints of the Carceri d'invenzione. Virtuoso pianist Vladimir Horowitz, who refused to perform this étude in public, said, "For me, the most difficult one of all is the C Major, the first one, Op. 10, No. 1."
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