The letters do not form a complete series, having been collected, with many blank sheets, for the sake of their watermarks, which are described by William Cramond, in 'Water-marks on Northern Letters', in ‘Glasgow Herald’, 2 January 1897 (folio iv). The written documents, which come chiefly from the papers of Alexander Gordon of Aberdour, factor to the Earl of Aberdeen, and of William Rose, factor to Earl Fife, deal principally with the families of Abernethy, Gordon, and Duff.