The patent granted to William Byrd and Thomas Tallis in 1575 to print both music books, except Psalm books, and ruled music paper draws attention to the close relationship between printed and manuscript production of music books. When printed and manuscript books for the period are considered together it becomes clear that their history is intertwined and that, for both categories, contents, layout and method of production were determined by the social contexts of their composition and their audience. Music writing with any speed and accuracy was a skill which took practice to acquire. The work of the London clergyman, Thomas Myriell, dating from the early seventeenth century, contains examples of presentation and working manuscripts. Music in Scotland, as also in smaller centres throughout Britain, was largely dependent on London for the supply of printed music books. By the end of the seventeenth century London was still the centre of music publishing.