Concertina | An Consairtín
A concertina is a free-reed musical instrument, like the various accordions and the harmonica. It has bellows, and buttons typically on both ends of it. When pressed, the buttons travel in the same direction as the bellows, unlike accordion buttons, which travel perpendicularly to the bellows.
The concertina was developed in England and Germany, most likely independently. The English version was invented in 1829 by Sir Charles Wheatstone, while Carl Friedrich Uhlig announced the German version five years later, in 1834. Various forms of concertina are used for classical music, for the traditional musics of Ireland, England, and South Africa, and for tango and polka music.