Back online again & after some weeks of slacking, re-playing Ghost of Tsushima, Final Fantasy VII Remake and Horizon Zero Dawn, my main computer is up and running again (tho' I did have to download a copy of the manual for the thing's mainboard before I could start it up) and I've actually kinda-sorta resumed serious work on Sloane 3824 (as well as toyed with the concept of making a collection of the "Invocation of Angels" texts from 3821 & 3825, but that will require a legible copy of the latter).
The date of 1649 claimed for Sloane MS. 3824 in A Book of Treasure Spirits is, as regards the two major divisions of the collection, at least a decade too early. The statement "now it is June 1649" occurs on fol. 48r in the course of a somewhat rambling piece arguing for the possibility of human colloquy with Angels. Even if this statement is credible, which is doubtful for reasons to be discussed, it would refer to when that particular passage was first written: however, that section of 3824 is not the author's holograph but a copy made by Elias Ashmole from another (now apparently lost) MS., as indicated on fol. 31r.
The immediately preceding section of 3824 (fol. 23-29) consists of a set of conjurations and rubric for evoking spirits, crudely nailed together from the Heptameron and the Ars Goëtia. The materials from the former work are verbatim or near-verbatim from the 1665 edition of Robert Turner's translation of Henry Cornelius Agrippa his Fourth Book of Occult Philosophy, of Geomancie, &c. &c. &c. (the 1655 edition left the conjurations untranslated) even down to an eccentricity of orthography, giving a terminus a quo for Ashmole's copy of "Longobardus" and the material following it in the same MS. book.
The material on fol. 32-52 consists of excerpts from a copy of the angel-magic treatise Janua Magica Reserata, which were copied by Ashmole as not being in his other copy of that work (now Sloane 3825). The Janua contains extensive borrowings from the translation of Agrippa's Three Books of Occult Philosophy by "J.F." (as Ashmole notes on 3824 fol. 30r), published in 1651. It also contains significant cribs from John Dee's spirit diaries, as published in 1659 by Meric Casaubon: indeed, the "June 1649" statement occurs directly before one such passage. The credibility of the date thus depends on the likelihood of (a) the passage in which it occurs having been originally written independently and later incorporated into the Janua and (b) the author having had access to Dee's spirit diaries in the Cotton library a decade prior to their publication. Given further that the general thrust of the entire section seems to be arguing for not merely the possibility of colloquy with Angels, but the compatibility of the angel-magic practices with the local form of Official Christianity, it makes far more sense to view it as a response to polemics like Casaubon's introduction to T&FR. This is leaving aside the high likelihood that the Janua was of common authorship with Clavicula Tabularum Enochi / "The Practice of the Tables" (Sloane MS. 307 / Sloane MS. 3821 fol. 2-157) which demonstrably depends on Casaubon's typeset for reasons that have been repeated ad nauseam.
The other major section of 3824, fol. 89-120 (a typeset of which forms the bulk of Book of Treasure Spirits) was an originally independent MS. book that was bound up with other items at some point prior to Hans Sloane acquiring the thing in Jekyll's estate sale. There are a few things giving it a terminus a quo: some borrowings from T&FR, which all occur towards the end (fol. 116r, 120v, discussed in previous posts). A design for a magic circle, in a similar hand to the rest of the book but on a loose leaf (fol. 105, not counted in that division's original pagination) is based on Agrippa's scale of the number 10 and perpetuates a printing error in the 1651 English edition, referring to the third Kabbalistic Sephirah as "Binah or prina" (in the table of the scale on p. 214 the correct Hebrew spelling and the familiar Romanized form are given; the misprint "prina" occurs on p. 368 (Book III cap. 10), where the 1533, 1550, 1567, 1578, 1600 and 1630 Latin editions (those were just the ones I checked) have "bina").
While this last is no further help in dating the MS., the final piece in that section, an untitled account of the three chief infernal spirits and four Kings of the quarters from the De officiis spirituum tradition, has strong parallels with the "Offices of the Spirits" section of the Folger "Book of Magic" (pp. 73 sqq.) although the conjurations and rubric have been rewritten (removing Roman Catholic elements for example), the descriptions of the chiefs have been redacted (omitting to mention that Beelzebub is wont to kill a magician who summons him without using the proper invocation and suffumigation, or that Satan will pester the invocant to pray for him to be restored to his former throne and place) and the bulk of the description of Egyn, King of the North, has unaccountably been omitted, the text cutting off (possibly due to a missing page in the scribe's source text) after the description of his nostrils.
