Not all gnostic literature comes to us from Nag Hammadi. A series of codices in Coptic have leaked out of Egypt and onto the art market down the centuries. One of these was the Codex Askewianus, as the older literature calls it.
On this item, the following information may be of use:
The Askew codex, a volume of unknown provenance containing the texts of the Pistis Sophia treatises, was named after its first owner, A. Askew, a London doctor. Askew was a collector of old manuscripts, and he bought the codex from a bookseller (probably in London) in 1772 . After the death of Askew, the manuscript was bought by the British Museum. A copy in the British Museum of the sale catalogue (1785) of Askew’s manuscripts contains the entry: “Coptic MS., £ 10.0.0.” This reference was presumed by Crum to apply to the present document which appears in his catalogue as Add. 5114.
1. J. G. Buhle, Literarische Briefwechsel von Johann David Michaelis, Leipzig 1794-6, vol. 3, p.69.
2. W. E. Crum, Catalogue of the Coptic Manuscripts in the British Museum, London, 1905, p.173.
Doubtless it emerged from the sands of Egypt, as other codices have done. One wonders how it ended up in London. The price is a considerable one, note: a curate around the same period could live (in poverty, admittedly) on £50 per annum, at least according to the novels of Jane Austen.
I was looking at some notes on this page, and came across the following footnote, alluding to the same source:
4. 1794. Buhle (J. G.). Literarischer Briefwechsel von Johann David Michaelis (Leipzig), 3 vols., 1794-96, iii. 69.
Under date 1773 there is a letter from Woide to Michaelis, in which the former says in reference to the [Pistis Sophia] Codex that Askew had picked it up by chance in a book-shop. There follows a description of the MS.
Now I confess that I never heard of Johann David Michaelis — he turns out to be an 18th century biblical scholar involved in orientalism –, but his letters are online at Google books. Volume 3, page 69 may be found here. The old fraktur letter forms are not easy to read, and the long-s is also deployed. The relevant passage may be this (and please correct my errors):
Vermutlich ist dieses ein ahnliches Manuscr. [of those in the White Monastery] Der herrn Dr Askew hat es zufalliger Weise in einem Buchladen gekauft. Es is in 4º auf Pergamen geschrieben, und sehr stark gebraucht. Es enthalt 354 Seiten, die mit Buchstaben numerirt sind. Jede Seite hat zwei Columnen; und es fehlt an dem ganzen Buche nur ein Bogen S. 337-345….
I had hoped that we might get more, but this seems to be it. Sadly this gives us no more than we knew. But how does C. A. Woide know this? What is his authority for this statement?
The letter as a whole begins on p.20, and seems to consist of a very lengthy description of Bodleian Coptic manuscripts.