DescriptionBritannica Trumpet Scale with Clarino Mouthpiece.png	English: Musical notation showing the notes which can be interpolated into the usual harmonic series when a mouthpiece of special design is used on a trumpet. The black notes represent the extra notes, which in the next octave transform the diatonic into a chromatic scale.
Date	1911
Source	Encyclopædia Britannica, 11th ed., Vol. 27, p. 325
Author	Victor Mahillon
Permission (Reusing this file)	Public domainPublic domainfalsefalse This image comes from the 13th edition of the Encyclopædia Britannica or earlier. The copyrights for that book have expired in the United States because the book was first published in the US with the publication occurring before January 1, 1929. As such, this image is in the public domain in the United States.

A curious phenomenon has been observed in connexion with the harmonic series of the trumpet, when the instrument is played by means of a special clarino mouthpiece (a shallow one enabling the performer to reach the higher harmonics), in which the passage at the bottom of the cup inaugurated by the sharp angle (known as the grain in French) is prolonged in cylindrical instead of conical bore for a distance of about 10 cm. (4 in.) right into the main tube. This peculiar construction of the mouthpiece, which might be considered insignificant, so upsets the acoustic properties of the tube that extra notes can be interpolated between the legitimate notes of the harmonic series. — V. Mahillon, La Trompette, son histoire, sa théorie, sa construction (Brussels and London, 1907, pp. 29-30).