The so-called 'Sadler partbooks' (GB-Ob Mus. e. 1-5), owned and probably produced by the Anglican priest, schoolmaster and translator John Sadler (b.1513), are a prime musical source. All five of its volumes survive complete (but for one folio in one partbook, that did not ec, and its pages contain Latin-texted motets, a Mass setting, part-songs, and a textless In nomine. The paratext to Sadler's partbooks is also unusually rich: scattered among their musical...