This manuscript contains a set of poems by James Nicholas of Denmark (he flourished c.1360-73) written in 1363 in honour of Aymer of Valence, Earl of Pembroke (d.1324), whose widow Marie was Nicholas's patron, and founder of Pembroke College, Cambridge. On a flyleaf it has a late medieval ownership inscription (partly erased) of the College. This diagram, headed '25th Metre', contains a poem laid out in a shield-shape to emphasise the poetic structure. The first line is read across the top; the second line is read from the top right corner towards the bottom; the third line is read from the bottom to the top left corner; the fourth is read diagonally across the middle; and so on. This makes clear that every line begins with a letter 'M' and every line ends with an 'S', and the word in the middle of each line begins with either an 'M' or an 'S'.