Thomas Morley (1557/8-1602) has long been regarded as the most important English music theorist of the early modern period. His treatise, A Plaine and Easie Introduction to Practicall Musicke was published in a luxurious folio format in 1597 and a second edition appeared in 1608. The three parts of the treatise set forth elementary music ('teaching to sing') and beginning and advanced counterpoint ('treating of descant' and 'treating of composing...