Two famous variation sets from the Baroque era , both originally written for harpsichord , are George Frideric Handel 's The Harmonious Blacksmith set , and Johann Sebastian Bach 's Goldberg Variations , BWV 988 .
George Frideric Handel wrote a famous set of variations for harpsichord called Harmonious Blacksmith , and Johann Sebastian Bach wrote the Goldberg Variations , which was a set of 30 variations : a very long piece of music .