The collection was compiled by Captain Robert Seton, Judge Advocate for Scotland, and consists of:
(i) Copies of correspondence, 1566-1567, of Sir Nicholas Throckmorton (folio 1) including two letters of Mary, Queen of Scots not recorded in Labanoff`s collection. The letters are similar to, but not the same as many of the letters in MS Calig CI from the Cottonian Library in the British Library: they may have been copied from the portion of the collection that was destroyed in the fire of 23 October 1731. Other 18th-century copies of this correspondence are at Adv.MSS.6.1.19, folios 148-156 and 34.3.13, folios 47-53.
(ii) `Chartae Authenticae Pro Legittima origine Regiae Stuardorum Stirpis in majori [sic] Brittania, ex Supplimento [sic] Johannis Mabillon de re Diplomatica` (folio 9). The documents were originally printed in ‘Charta authentica Roberti Seneschalli Scotiae; ex Archivio Collegii Scotorum Parisiensis edita’, and reprinted in ‘De re diplomatica’, 2nd edition, Supplementum pages 102-109, from which this copy was made, in a different order, and without the reproductions of the seals.
(iii) Copy of a letter, 1559, of Quintin Kennedy, Abbot of Crossraguel to James Beaton, Archbishop of Glasgow (folio 27) followed by a copy of a disputation between Kennedy and John Willock. Both items are printed in ‘The History of ... the Affairs of Church and State in Scotland’, Appendix pages 192-199, `from the original in the Scots College, Paris’.
(iv) Copies of documents dated between 1419 and 1559 relating to members of the family of Sinclair of Roslin (folio 34 verso). These may derive from, or from the same source as, those by Richard Augustine Hay at Adv.MS.34.1.9(ii), folios 153 verso, 162 verso, 170 verso, 279 verso, 298, 259 verso, 165 verso. The testament of Alexander Sutherland (folio 35 verso) is printed from the original in the ‘Bannatyne Miscellany’, volume iii (Edinburgh, 1855), pages 93-102.
(v) Copy of the charter, 1493, of George, 2nd Lord Seton, following papal authorization, 1492 (cf. Adv.MS.15.1.19, number 15) establishing the church at Seton as a collegiate church (folio 47).
(vi) Copy of `The Inventary of the Silver work of St Machir in Old Aberdeen ... 7th July 1559 ... ` (folio 50).
(vii) Lists of monastic houses (folio 52 verso) and dioceses (folio 56 verso) in Scotland, from an unidentified source,
(viii) Observations on ‘Charta authentica Roberti Seneschalli Scotiae ...’ by Lewis Innes (folio 58; cf. folio 9 and what follows), headed in an apparently different hand `This is Father Hay`s letter to the Earle of Perth Upon the Papers published att Paris by Mr. Innes concerning the Legitimacy of K: Robert 2[??] Marriage with Elizabeth More`. It appears not to have been printed.
(x) `Coppie` (probably an extract) of a letter of Roger Maxwell, Society of Jesus, to R A Hay concerning the Scots College, Douai, undated (probably in or soon after 1712) (folio 72).
(xi) `Letter from Mr. Thomas Innes ... to Mr. Robert Keith ... 18 April 1730` enclosing copies of manuscripts and documents taken from a collection of papers in at least thirteen volumes apparently entitled `Memoirs of Scotland`, which was then at the Scots College, Paris, and a few copies from manuscripts in the Cottonian collection (folio 73), all relating to affairs of state including copies of correspondence of Mary, Queen of Scots 1558-1568, 1576-1577.
(xii) Copies of correspondence and papers from a manuscript containing state papers during the early years of the reign of Mary, Queen of Scots (folio 102). This manuscript is referred to in ‘History of ... the Affairs of Church and State in Scotland’, page 147 and described at page 154 note (a): `... This Manuscript is in the Laigh Parliament- house, Edinburgh. It is exceedingly much defaced and eaten away at the corners, few Lines only being legible in a great many Places, and sometimes only a few Words here and there. It contains miscellaneous Papers of State during the Reign of Queen Mary.` As no manuscript answering this description has been identified amongst the Advocates` Manuscripts or those at the Scottish Record Office, it seems likely that the source for these transcripts has disappeared. Amongst the papers are several letters of Mary, mainly to Elizabeth: several are printed in ‘History of ... the Affairs of Church and State in Scotland’, but those that were not were not known to Labanoff. Following this is a copy of a letter, 1731, of Innes to Keith (folio 178).
(xii) Contents list (entitled `Index`) (folio 180).
The volume is written in two hands, folios 1-8 verso, 78 verso-83 verso, 86-94, 175 verso-177, the headings at folios 58, 73, and a few marginalia elsewhere (for example folios 28 verso, 29 verso, 30 verso, 31 verso) being written in a hand, presumably Seton`s, belonging to the early years of the 18th century, the rest of the volume belonging to a slightly later hand.