1911 Encyclopædia Britannica/Rackett
|←Rack||1911 Encyclopædia Britannica, Volume 22
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RACKETT, or Rackett-Bassoon (Fr. cervelas or cervdat; Ger. Rackett, Rankett or Wurstfagott), a kind of dwarf bassoon, now obsolete, with a body measuring only from 4½ to 11 in. in length, but nevertheless containing the necessary length of tubing to give the bassoon or contra-bassoon pitch. The rackett consists of a barrel-like body, resembling the barrel drone of the musette (see Bagpipe), made of wood or ivory. Round a centre tube are grouped eight parallel channels of very narrow cylindrical bore communicating with each other and forming a continuous tube nine times the length of the small body.
A reed mouthpiece in combination with a cylindrical tube invests the latter with the acoustic properties of a closed pipe by creating a node at the mouthpiece end; the fundamental note given by such a tube is, therefore, an octave deeper in pitch than would be an open pipe of the same length. The bassoon has a conical bore and the properties of the open pipe, wherefore the aggregate length of the channels in the rackett only requires to be half that of the bassoon, a physical phenomenon to which this curious freak owed its existence. In the rackett the holes are bored obliquely through from the channels to the circumference — three in front for the left and three for the right hand, with an additional hole for the little finger; while at the back are placed the vent and three holes, one for the left thumb and two for the right, the second hole being controlled by the ball of the thumb. The rackett is played by means of a large double reed placed within a pirouette or cap, so that the lips do not come into contact with the reed, but only send a stream of compressed air into the pirouette, whereby the reed is set in vibration. The consequence of this principle of construction, peculiar to the bagpipe chaunter and drones (with a slight variation) and to cromornes, hautbois de Poitou and a few other obsolete instruments, is that no harmonics can be obtained, since the vibrating length and the tension of the reed cannot be controlled by the player; the compass is therefore pbtained by means of the fundamental and of the ten holes of the instrument, aided by cross-fingering. (K. S.)