The bark will then be stripped off by machetes or other devices. Then the length of timber will be checked or tested for any cracks or holes. Both ends of the wooden tube will be covered by hands and kept under water for a few minutes. If bubbles appear, it means that there are holes and these should be sealed with beeswax. It is similarly designed with the piano which has the ability to play each tone in all octaves. Traditionally, it has eight to sixteen holes in intervals of two. The regular chromatic harmonica uses the slide to produce some of the notes in a complete chromatic scale which is recurring at each octave. Oboe s structure Traditionally, oboes are made of granadilla or African Blackwood and have three sections top joint, bottom joint, and bell section. The left hand controls the 10 holes on the top joint while the right hand is used for the also 10 holes on the bottom joint. Covered with keys are two holes in the bell section. Fipple flutes are easier to play and has a distinct timbre compared to other flutes. Here are the categories of flutes based on origin: 1. Western concert flutes The western concert flute is a descendant of the German flute. It is closed at the top and the embouchure hole is placed near the top. The regular concert flute can play three octaves beginning from middle C which gives it one of the highest pitches in the orchestra besides the piccolo. Sound is produced through plucking strings whenever the respective keys are pressed. Pressing a key raises the designated plectrum on another end. The string is plucked by this and this turns so it does not make contact with the string downwards. History The harpsichord was invented in the Middle Ages. It is also referred to as mandole and has a scale length of approximately 20 inches. The sopranino or piccolo mandolin is pitched an fourth of an octave higher than the mandolin. Mandolin styles There are six mandolin styles the Neapolitan bowlback, a-style flatback, f-style flatback, Maccaferi style flatback, solid body electric, and electro-acoustic mandolins.