Complex sentence: The only extant manuscript, in the private possession of the Earl of Dalhousie and kept at Brechin Castle, Scotland, is fragmentary; the "Historia" itself is found on folios 1r-12r.
Split into simpler sentences: The only extant manuscript is in the private possession of the Earl of Dalhousie, and kept at Brechin Castle, Scotland. However, it is fragmentary; the "Historia" itself is found on folios 1r-12r.