Iolo Morganwg
In 1916 Sir Ivor Herbert deposited the Llanover Manuscripts in the National Library and his daughter later converted the deposit into a donation. The Llanover Manuscripts comprise seventy-seven volumes of notes, transcripts and compositions in the hand of Edward Williams (Iolo Morganwg) on a wide variety of subjects including druid mythology, bardism, fruit culture, geology and medicine, and more than forty further volumes of Welsh manuscripts dating from the late sixteenth to mid-eighteenth century and mostly originating in Glamorgan, which Iolo Morganwg acquired.