A Dictionary of Music and Musicians/Non plus ultra
NON PLUS ULTRA, the title of a pianoforte sonata in F by Woelfl (op. 41), published in 1807 (?), and intended to express that mechanical difficulty could no further go. The finale is a set of variations on 'Life let us cherish.' The challenge was answered by 'Plus ultra,' the title affixed by the publishers to Dussek's sonata 'Le retour à Paris' (op. 71) on its publication in England.
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