cornet, brass wind musical instrument, created in France about 1830 by adding valves to the post horn. It is usually in B flat and is the same size as the B flat trumpet, but has a more conical bore. The cornet, a transposing instrument, has a less brilliant tone but greater agility than the trumpet. It has long been a standard instrument in bands. In the orchestra, the cornet is used with the trumpet. It was used extensively in jazz in the early 20th cent. It should not be confused with the cornett, an instrument of the Middle Ages and Renaissance, which used a cup mouthpiece on a wooden or ivory body supplied with fingerholes similar to those on woodwinds. A bass cornett was used until the early 19th cent.

Gaudí i Cornet, Antonio, 1852-1926, Spanish architect. Working mainly in Barcelona, he created startling new architectural forms that paralleled the stylistic development of art nouveau or modernismo. Many of his buildings resemble sculptural configurations; examples are the bizarre structures in the Park Güell (1900-1914) and the undulating facades of the Casa Battló (1905-7) and the Casa Milá (1905-10). Gaudí also introduced color into his facades. Improvising designs from odd bits of material, such as rubble, bricks, and polychrome tiles, he achieved variegated effects, evoking comparisons to abstract expressionism and surrealism. Gaudí is as remarkable for his innovations in technology as for his aesthetic audacity. He ingeniously constructed various devices that enabled him to achieve his unusual building shapes; he is particularly admired for his use of the hyperbolic paraboloid form. The Expiatory Church of the Holy Family (begun 1882) represents the height of Gaudí's achievements. It was never completed, and work continues on the structure.

Valved brass instrument. It evolved in the 1820s from the posthorn. Like the trumpet, it has three valves, but its bore is somewhat more conical. It is a transposing instrument (its music written a tone above the actual sound), usually built in the key of B-flat, though a higher-pitched E-flat instrument is used as well. Its range parallels that of the trumpet. Its agility made it a very popular solo instrument; it often displaced the trumpet in 19th-century orchestras, and it preceded the trumpet in modern dance and jazz bands. Recent developments have made the two instruments very similar, and the cornet's popularity has waned considerably as a result.

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