By this time Debussy was ill with colorectal cancer. His visit to London in 1914 was his last trip to another country. He wrote more piano works: a set of Études and a piano duet called "En blanc et noir" ("In white and black"). He planned to write six sonatas, each for a different group of instruments, but he only wrote three of them: one for cello and piano, one for flute, viola and harp and one for violin and piano. The "Sonata for violin and piano" (1917) was the last work he played in public (he played the piano part). He died of colorectal cancer in 1918.