L'estro armonico National Library of Wales in Aberystwyth. The 1797 Encyclopædia Britannica records that the fifth concerto was also played on an Irish variant of Benjamin Franklin's celebrated invention, the glass harmonica. Under the entry for "Harmonica" or "Armonica", a 35-glass harmonica is described, about which its inventor, the Dublin physician Edward Cullen, writes: There were numerous arrangements for keyboard instruments in the eighteenth century, as described in the next section. One surviving eighteenth century transcription of Op.3, No.3 has been interpreted as an arrangement for glockenspiel. Themes from movements in the concertos were borrowed by other composers for vocal works: the
Glass harmonica Franklin wrote from London in 1762 about his musical instrument: "The advantages of this instrument are, that its tones are incomparably sweet beyond those of any other; that they may be swelled and softened at pleasure by stronger or weaker pressures of the finger, and continued to any length; and that the instrument, being well tuned, never again wants tuning. In honour of your musical language, I have borrowed from it the name of this instrument, calling it the Armonica." In Franklin's treadle-operated version, 37 bowls were mounted horizontally on an iron spindle. The whole spindle turned by means of