And I've come to the end of Book 1! I first learned this in 2016, at the end of a personally difficult year. The total playing time is around 9 minutes; the versions I recorded varied between 8 minutes 49 seconds and 9 minutes 2 seconds, which doesn't look like a huge variation, however, in the shorter version I played the prelude too quickly. It is quite a long piece, in binary form with both sections repeated. And then the fugue with its plaintive subject featuring sighing appoggiaturas stretches over 6 pages before ending, as usual in the minor keys, on a Tierce de Picardie.