Bundles of music manuscripts mostly in the hand of Iolo Morganwg, including a file of traditional music, previously 'IAW 145' (E1/1); manuscripts of a few further traditional tunes (E1/2); bundles of miscellaneous music manuscripts, including salmau, traditional music, English tunes, etc. (E1/3-5); and loose leaves originally belonging to a single tune book (E1/6).
The contents of E1/1 have been published in Alawon Gwerin Iolo Morganwg, ed. by Leila Salisbury (Aberystwyth, 2012), together with six further tunes (Nos. 4, 5, 17, 28, 40, 50) designated 'IAW 145 (uncat.)', all now to be found in E1/2.