Orlando does in fact travel through a time tunnel for hundreds of years, so this is less of a metaphor than it seems. The real metaphor lies in that quickening of his – by now her – senses as if a tuner had keyed her nerves to tautness as tightened piano wires.
‘… as she was thinking this, the immensely long tunnel in which she seemed to have been travelling for hundreds of years widened; the light poured in; her thoughts became mysteriously tightened and strung up as if a piano tuner had put his key in her back and stretched the nerves very taut; at the same time her hearing quickened …’
Source: Virginia Woolf, Orlando: A Biography, ed. with an introduction by Rachel Bowlby (Oxford: World’s Classics, 1992), p. 284
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