A Dictionary of Music and Musicians/Augmentation
AUGMENTATION. This term is used to express the appearance of the subject of a fugue in notes of double the original value, e.g. crotchets for quavers, minims for crotchets, etc., and is thus the opposite to Diminution. Or it is a kind of imitation, or canon, where the same thing takes place. Dr. Benjamin Cooke's celebrated canon by double augmentation (engraved on his tombstone) begins as follows, and is perhaps the best instance on record.
We subjoin by way of example one of a simpler kind by Cherubini.
When introduced into the development of a fugue, augmentation often produces a great effect. As examples we may cite the latter part of Handel's chorus 'O first created beam' in 'Samson'; the concluding chorus of Dr. Hayes' anthem 'Great is the Lord'; Dr. Croft's fine chorus 'Cry aloud and shout'; Leo's 'Tu es Sacerdos' in F, in his 'Dixit Dominus' in A'; and several of J. Sebastian Bach's fugues in his 'Wohltemperirte Clavier.' The old Italian church composers were very fond of introducing augmentation, especially towards the end of a choral fugue, and in the bass. They would call it 'La fuga aggravata nel Basso.' Fine examples are found in 'Amens' by Leo, Bonno, and Cafaro, in Novello's Fitzwilliam music.
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