An Historical Summary of Angelic Hierarchies from Part VII: The “Seven” Thrones in In Operibus Sigillo Dei Aemeth by David Richard Jones.

“In the first section below and the text following it, not given but to which the careful reader is referred, the hierarchy is fairly strictly that of Saint Gregory and Denis. In the second section here we have a threefold division according to the lower planetary spheres, exactly along the lines given in the passage describing the principle hierarchies of the Sigillum, that is Thrones, Archangels (or as demonstrated above Trumpets) and Angels. And in the final section we see that Thrones are assigned to the motions of the heavenly spheres. This is the function they seem to have in the overall structure of the Sigillum and which clearly relates to the magical theories of Dee’s own Propeadeumata Aphoristica.” [via]