ANGELS AROUND THE CRYSTAL
THE PRAYER BOOK OF KING WLADISLAS
AND THE TREASURE HUNTS OF HENRY THE BOHEMIAN 
Introduction: Crystallomancy and Ritual Magic
Written evidence on the medieval practice of crystal magic is rather scattered and fragmentary; still, its basic rules can be reconstructed . In his survey of magic, William of Auvergne, bishop of Paris (ca. 1180-1249), presents the use of crystal balls (more precisely the inspection of shining bodies, inspectio corporum lucidorum) in order to see revelations as a method of natural magic, which nevertheless may turn out to be dangerous and demonic, partly because looking into the transparent body may damage the viewer's eyes, and partly because malign spirits may interfere even if the operator did not intend to invoke them. It is clear in this report, that the practice of crystal balls (crystallomancy), magical mirrors (catoptromancy), and other shining bodies (such as fingernails, swords, ivory objects and basins filled with water) with its detailed methodology and well-defined procedure of ritual invocations, was not a mere sub-branch of natural – i.e. non-demonic – magic  and pure divination . It transgressed irreversibly the borders of the realm of ritual (or ceremonial) magic which functions through the invocation of angels and demons and which often involves young girl and boy mediums who get into contact with the spirits .
In 1376, Nicolaus Eymeric, the famous Catalan inquisitor who had a close acquaintance with necromantic books, since he read, condemned and burned many of them, also reported about invocations, which might be performed 'by tracing a circle in the earth, by placing a boy in the circle, by fixing a mirror, a sword, an amphora, or other small body before the boy, and with the necromancer himself holding a book, and reading, and invoking the demon' . In his exhaustive catalogue of divinatory techniques, Das Buch aller verpoten kunst, the German Johannes Hartlieb (ca. 1400-1468) reports cases of scrying with steel mirrors: these should be consecrated, and then – according to the magicians – angels and not demons appear in them .
An anonymous necromantic manual, now published by Richard Kieckhefer, also contains accounts of experiments with gazing into crystals, which aim at obtaining information about uncertain things, such as a theft . This crystal is put to work, or rather "switched on" by names of God (Adonay, Sabaoth, Hel, Hely, Sother, Emanuel, Alpha et O, and so on), and if all the indispensable ingredients are at the disposal of the magician, he may start conjuring angels, who will tell him the truth . One of these elements necessary for the crystallomantic and catoptromantic activities, as well as for a wide range of other divinatory experiments and invocations described by the necromantic handbook, is a virgin boy . That young boy mediums are essential in many magical rituals is testified by other sources as well. John of Salisbury, William of Auvergne, Johannes Hartlieb and Nicolaus Jawor unanimously mention virgin boys used as mediators of the divine message , John of Salisbury having the most personal experience among them, since he himself was used in his youth by a priest as a recipient of divinatory information (Policraticus, II. 28) .
A fairly analogous picture of crystallomantic procedures operating with a similar magical apparatus emerges from the documentation of legal procedures led against real or alleged magicians. From Jean de Bar's famous confession of 1398, we learn that he consecrated a crystal stone in order to enclose in it a devil, whom he mistook for a benign angel, and during all these events a child was also present . Jean describes the ritual components of his practices in great detail: how he (ab)used the elements of Christian liturgy, and how he applied figures, characters, images, the holy names of God and strange words (estranges paroles) during the invocations. The demons invoked through these rituals later enter a consecrated mirror, tell the operator all the secrets they know, and answer honestly whatever is asked from them . All these methods and convictions were – as Jean confessed before his execution – taken from special necromantic manuals.
Another curious and rather unknown text on crystal scrying is again a confession,
this time made by a certain William Byg alias Lech . This magician arrived in South Yorkshire in 1465, and for the following two or three years lived by recovering stolen property with the help of a crystal. In his confession made in front of the Commissary Poteman in 1467, William Byg admits how he performed his practices with the help of a sixteen-year old boy, with a crystal stone, and through prayers to Christ and the angels. As a result of all the preparations, the boy could see one or two angels thus invoked appearing in the crystal, and these angels were willing to answer questions about the location of the stolen articles. The question to be asked of the conjured angel is spelled in English in the otherwise Latin confession: 'Say me trewe, chylde, what man, what woman, or what childe hase stolne yis thyng, and shewe me thing in his hand'. Through these procedures – the confession goes on – William managed to reveal the location of numerous precious stolen properties belonging to various noblemen, among them a Fitzwilliam (whose involvement could be the main reason why William was not condemned to death as Jean de Bar was). Finally, this text also ends with a statement that all these methods were learned from magical handbooks, and that the angels appeared through the reading of these books.
As is apparent from the sources, by the end of the Middle Ages, a comprehensive procedure of crystallomancy is worked out with a well-defined list of participants, tools and convictions. Consciously summoned angels appear in the crystal to answer the questions of the operator (most often about the location of hidden treasure or stolen articles but occasionally also about the highest truths), virgin boys serve as mediums, magical handbooks provide the appropriate formulae to be read, and consecrated crystals are engraved with the secret and powerful names of God. These elements go far beyond the territory of natural magic (allowed by William of Auvergne as a legitimate science), and consequently they provoke certain worries and serious counterattacks from the side of official theology: inquisitors and university statutes condemn it, while its practitioners are called before the court, made to confess their errors, and are even executed occasionally. Aware of all this, the historian does not tend to expect a handbook of crystallomancy to be tolerated by official authorities and to occur – and more importantly: to be used – say, in a royal library. Yet, in the following, we will examine a Polish royal prayer book which combines crystal gazing with the basic texts of ritual magic, and which – as I will attempt to demonstrate – is related furthermore to a court case most similar to that of Jean de Bar and William Byg.
The Prayer Book of King Wladislas
The illuminated prayer book, now preserved in the Bodleian Library , known as the Modlitewnik Władisława Warneńczyka (Wladislas Warnenczyk's prayer book), was at the center of scholarly interest as early as 1928, not only because of its peculiar content, prayers, miniatures and instructions on pursuing crystallomancy, but also for the mysteries around its history and owners .
Originating in fifteenth-century Poland, this is one of the eight prayer books known to have belonged to the famous royal family, the Jagiellonian dynasty . It is, however, the most complex, enigmatic, and atypical among them. Eighty parchment folios supply the reader with a number of prayers of various provenance (mostly deriving from prayers in common use), addressed to Christ, the Virgin Mary, and the Holy Spirit. However, in most of the prayers we find inserted a stereotypical crystallomantic formula with reference to a crystal ball, to various angels, and to the person for whom the book was meant. Wladislas, the unworthy sinner and servant of God  – so the text goes – prays for the angels to clarify and illuminate (sometimes to enter, open and amplify) the crystal in order that he may learn all the secrets of the world. These formulae introduced in the text of the prayers vary slightly in length and wording, but they are highly similar and have the same structure:
– Ad vos clamo, rogo humiliter et devote Ego Wladislaus, indignus peccator, nullis meis meritis confidens, sed peccatorum mole gravatus... 
– Da et huic Cristallo et michi indigno famulo tuo Wladislao ad exercendum in eo cunctipotencie tue omnipotencieque virtutem... 
– ...ad videndum in illo Cristallo omnia secreta, que sub quatuor elementis contenta sunt, et omnia que scire voluero... 
– Quatenus super me respicere digneris, indignum famulum tuum Wladislaum, et michi in hoc Cristallo veram visionem per sanctos angelos ostendere digneris... 
– Da michi, domine (...) hunc Cristallum (...) ut in eo videre possum Omnia, quecumque voluero, que sub quatuor elementis continentur secreta (...) et impartire michi hanc graciam super hunc Cristallum, sicut Impartitus es regi Salomoni et posteris suis artibus... 
– Mitte michi sanctos angelos tuos ad huius cristalli clarificationem et illuminacionem ut omnia huius mundi secretissima secreta sub quatuor elementis contenta... 
– Mittat sanctos angelos suos ut me instruant ad videndum in eo omnia que in mundo, in terra vel sub terra sunt, sub quatuor elementis contenta... 
– Digneris hodie inspirare in cor meum huius Cristalli, per sanctos Angelos tuos, ad clarificandum et illuminandum, ut in eo videre valeam et considerare omnia que sub quatuor elementis contenta sunt, et secretissima mundi, sine nocimento et omni lesione mentis et corporis, per spiritus sancti graciam... 
And so the petitions continue, permuting the same expressions about Wladislas and his crystal, about God and his angels, and about the ways the secret knowledge may be revealed. The excerpts quoted above designate the three issues on which we will concentrate in the following: the text of the prayers, the crystal, and the operator – which latter issue may be divided into two sub-questions: the identity of Wladislas, the owner, and the identity of the anonymous author of the prayer book.
Text and Sources
In his detailed study introducing the edition of the text, Ryszard Ganszyniec identified the provenance of roughly two thirds of the prayers . Most of these were standard liturgical texts, common Mass prayers and private devotional prayers collected from the core of the medieval prayer books. Nevertheless, Ganszyniec identified one prayer (Summe deus pater piissime) as deriving from a magical source attributed to Solomon, the Ars notoria . This text is a most widespread example of medieval ritual magic and theurgy; it promises intellectual perfection, learning, the acquisition of memory, and understanding difficult books by means of a large variety of prayers, invocations of divine and angelic names and numerous rituals.
The Ars notoria prayer borrowed by Wladislas' book originally aimed at gaining intelligence and memory, but in its new context it was altered with the insertion of the standard petition to God to send his angels to illuminate the crystal. This text is not present in the earliest versions of the notory art; it belongs to a short version that was later attached to the main bulk of the Ars notoria, and appears as a closing prayer in the first printed version, which can be read in a sixteenth-century edition of Cornelius Agrippa's Opera Omnia . What is interesting here (and what leads us to certain speculations) is the fact that the following prayer in the prayer book of Wladislas also contains an Ars notoria excerpt (O lux mundi) , again occurring in Agrippa's volume but fifty pages earlier than the other one, completely separated . In contrast, it appears just next to the Summe deus prayer in another Polish codex, the MS Biblioteka Jagiellonska (henceforth: BJ) 551, in a short version of the notory art (f. 109v-111r). It is quite likely therefore, that a short Ars notoria version containing these two prayers next to each other traveled in the medieval manuscripts, and the compiler of the prayer book worked from a text similar to the one in BJ 551 .
Ganszyniec left a number of prayers unidentified, but he claimed that the author worked in a continuous and uniform way, borrowing pieces of texts from his sources, and not composing a single prayer himself. The author, who is rather a compiler, seems to have been satisfied with introducing formulaic paragraphs quoted above into the imported texts. More recently Urszula Borkowska examined the prayers of Wladislas in the context of other prayer books of the Jagiellons, and she noted that 'Marian devotion is particularly developed in it, and the angelological texts, rarely developed in prayer books, are extremely interesting' .
Ganszyniec and Borkowska are not to be blamed for leaving the most important source of the author of the royal prayer book unidentified; they were simply not in a position to find this source, since the Liber visionum of John of Morigny was not at the center of scholarly interest in the time they completed their books. John of Morigny was a French Benedictine monk, with some university training behind him. He once practiced the notory art himself, but for various reasons he found it demonically motivated, abandoned it, and inspired by the Virgin Mary he decided to prepare a purified version of the Ars notoria. Thus, he composed an exceptional collection of Marian visions, the Liber visionum. The Church authorities were not convinced by the monk's confidence that his work was delivered by the Virgin Mary, and the Liber visionum was officially burned in Paris in 1323 . Although John's book has been discovered just recently, and was virtually unknown by earlier scholarship, a number of accurate studies published in the last ten years seem to make up for this previous disregard . Meanwhile, new manuscriptsare continually turning up, and the edition of the text is also under preparation; so far, however, only its autobiographical prologue is accessible .
As Claire Fanger and myself pointed out , almost one third of the prayersin Wladislas' prayer book go back to Brother John's text. Among these, we find the prayer which Ganszyniec supposed to have been borrowed from erotic literature , as well as the closing angelological prayers that Borkowska found exceptional and without analogy . These prayers are addressed to God (such as O Rex regum, qui es fortissimus...) , to the Virgin Mary (Ave, salve gloriosa mea amica, virgo maria, and O Gloriosa regina angelorum) , to the four archangels (Et rogo vos Archangelos Michael, Gabriel, Raphael, et Uriel, et invoco vos, ut illuminetis Cristallum illum...) , and to the hierarchyof angels (O vos omnes spritus sancti angelici, benigni, gloriosi, dulces et mites, qui in ordine angelorum, in inferiori Yerarchia loca et mansiones habetis) . Although the borrowings are somewhat unsystematic and in most cases the author did not adapt complete prayers, rather mixing, interpolating and abbreviating excerpts from various parts of the Liber visionum, still the order of the extracts more or less follows the original sequence. Interestingly, the author of the prayer book incorporated in his text those parts of the Liber visionum where John describes how he – blindly – used to practice the Ars notoria, before turning away from this wicked and demonic art: Oro te, supplico tibi, rogo te toto corde meo, quia prius et antea, quodam suffocacione demoniaca tentatus decepcione, illo prevalente, cecatus, quasi hesitans, non credendo revelaciones sacras et moniciones michi ex bono spiritu, operacione et arte, quibus ignoranter vacaveram esse factam, et in detrimentum anime mee ad diversas peccatorum operaciones quasi scienter cucurri et, prochdolor, adhesi mei in contumeliam creatoris .
As a matter of fact, this is the first text in the prayer book borrowed fromthe Liber visionum (in the original it was not a prayer), and it follows the Ars notoria prayer. It is mainly this positioning that has led Claire Fanger and myself to the conclusion that the author of the prayer book must have known John's whole text, and consciously imitated the structure of the Liber visionum, as well as John's passage from the Solomonic art in his own angelic system . The impression that John and consequently our author are no longer offering diabolically motivated magic in their books, but are trying to do something non-demonic and divinely inspired, is reinforced by many later claims in the text: ... et omnes temtaciones dyabolicas omnesque fraudes et artes magicas valeam devitare et viriliter superare... 
Another interesting motif borrowed from John is the emphasis on the care with which the book itself is prepared. Relying on the text of the Liber visionum, although somewhat altering it, our author also stresses that the book was written, made and composed with great diligence, devoting to it several days, hours and nights with vigilance, fasting, special orations, complete reverence and many ceremonies . This ritualistic attention to the preparation of the book is unknown in the tradition of the Ars notoria. For parallels we have to turn to other magical sources, either to the Liber consecrationis, in which the book is not only prepared with such care, but is also consecrated , or to the Liber Juratus, at the center of which we find again a consecrated book. The latter one narrates the event when a synod of 89 necromancers and magicians  gathered together from Naples, Athens and Toledo and they chose from among themselves a leader, Honorius, son of Euclid, who wrote a book on the magical arts which contained the hundred sacred names of God. This book is called the sacred or sworn book of Honorius, because – as the text stresses – it is consecrated by God and His angels . The act of consecrating a magical book indicates expressively the difference between a text of magical content and the book as an object enclosing the text.
Still there remain a few prayers the sources of which are not identified by Ganszyniec as devotional texts of common use; nor do they come from brother John. One of these is a prayer addressed to Adonay (Rex potentissime, omnium creaturarum visibilium morabilis dispositor)  which is copied in a significant place: after the Ars notoria prayer, and before the first borrowed passage from John, while it also incorporates the aforementioned short paragraph from the notory art. This prayer is rich in magical elements; among them we find the main motif of natural magic: the occult virtue of gems and herbs induced by God (qui virtutem das cunctis gemmis et herbis, da et huic Cristallo ... cunctipotencie tue virtutem). These paragraphs are either composed by the compiler himself, or borrowed from an as yet unidentified magical source. An additional reason why they are of interest for us is that they contain some interesting details about "the crystal", details that are not to be found in the other parts of the book. Interestingly, the crystal appears here as a quadrangular object (qui quadrangularem hunc Cristallum illuminet), and functions – as the text goes – through the "holy" (or, rather, magical) names of God: Agla, Sabaoth, Tetragrammaton, Emanuel and Messias  (the same names are often used in magical rituals, among other places in the necromantic manual from Munich) . It may be plausible to suppose – although it is far from being explicitly stated – that these divine names that offer their virtue to the crystal and function as powerful catalyzers of the process, are physically engraved either directly on the gem or rather on a metal frame surrounding it: coram presenti figura, tuo nomini reverenter fabricata et conscripta .
Although the crystal is at the center of the practices described by the prayerbook, about its appearance we only have conjectures based on analogies (note that there is no crystal involved in the practices of the Ars notoria, nor in those of the Liber visionum). A recently found and exceptionally well-preserved object may help us in speculating. German archaeologists excavated an elaborate magical mirror from the sixteenth century in 1999 near Mecklenburg . The small object (12 cm high) has a handle and a circular main part, in which in the middle of a drawn square we find a 3 cm rock crystal. Around the crystal, in the (quadrangular!) square, we read engraved the names of the four evangelists (on one side) and those of the four archangels (on the other). Outside the square are written those divine names which we know from the prayer book: Adonay, Messias, Tetragrammaton and Sabaoth, while along the perimeter of the outer circle, there are further powerful names, such as Agla, Eli, Eloy, rex, alpha et o, and Sabaoth again. No doubt this practically shaped object once served practical purposes, but who can tell today what (or whom) the practitioner saw when looking at the crystal, and what his source was, from which he read the instructions and the prayers?
Reading the Polish prayer book, it is not an over-interpretation of the text to expect that the crystal – if it was an existing object indeed – looked very much like the German device. While we cannot take it for granted that it really existed, we have every right to suppose so. The reader of the prayer book does not get any instruction on how to prepare it, and what is more, at one point – where the operator invokes the angels for the composition of the crystal (whatever this means) – he speaks about a present crystal . The text leaves no doubt that these are the angels who prepare the crystal, but seemingly they have already done this in the past, and they are not being asked to do so in the present. In addition, preparare seems to mean in this context "making it ready for being used", instead of "creating" .
Further crystallomantic instructions that we find scattered on the folios of the prayer book are not very helpful when we try to imagine how the object functioned. The picture put together from these small bits of information is rather obscure. The angels invoked through the prayers enter and amplify the crystal (intretis illum Cristallum et dilatetis eum) , then clarify, illuminate, and illustrate (Mitte michi sanctos angelos tuos ad huius cristalli clarificacionem et illuminacionem  and ut ad illum Cristallum pro illustracione at illuminacione istius) , and at the end of the preparatory stage for the vision, they even open it (quatenus dilatare et aperire digneris hunc Cristallum per sanctos angelos tuos  and ut tu cristallus scindas te et clarificas) . A last important detail is provided by the statement that the angels are also supposed to consecrate the crystal . Now, the consecration of a magical object (a crystal, a sword or a book) can be easily accounted for, and the clarification and the illumination of a crystal by the angels at the moment when it becomes a means of communication between terrestrial and celestial agents would still be understandable , but what do amplification (dilatare) and opening (aperire) mean?
Taking a look at the fourteen miniatures inserted amongst the prayers does not shed much light on this obscure picture. On most of them, we see a young crowned person with a white eagle on his coat of arms (the symbol of the Jagiellonian family), kneeling and praying in front of the Madonna (the orientation of the Liber visionum is faithfully adapted), to the crucified or the resurrected Christ, or to various saints . One of these illuminations filling the space just between the Ars notoria prayer and the first Liber visionum text (which narrated how Wladislas turned away from his previous magical practices) depicts the young crowned man with a sword (an important part of the magician's inventory, not only, but particularly in catoptromantic and crystallomantic experiments) in his hand, standing next to a table with a strange object on it, which mostly resembles three intersecting circles. The last miniature but one shows the same man kneeling in his chamber in front of the same object on a table, and behind the table three winged angels appear, while a Godlike figure seems to supervise the whole procedure. These angels are supposedly just in the process of illuminating, clarifying and entering the strange object, which should be – according to this interpretation – identified with the crystal. Needless to say, this depicted object does not bear any resemblance to the German mirror, and nor it is quadrangular as the text claimed. However, its shape is not very far from the "circles" described in a late medieval magical text, the Clavicula Salomonis  (four circles situated at the four angles of a square . As is detailed in its chapter on the construction of the circle, the practices of the Clavicula involve a consecrated magical sword with which the operator is to draw the circle , and some prayers to God (Lord Adonai), in which He is asked to enter and consecrate the circle which is marked out with the most powerful and holy names of His, and also to magnify and extend upon the operator . Although the first surviving manuscript of the Clavicula is from the mid-fifteenth century, it is likely that this text had earlier copies too , and – more importantly – the practices described in it may definitely originate from the late Middle Ages .
I do not want to imply, of course, that the author of the prayer book had an early copy of the Clavicula Salomonis in front of him. The point I am trying to make is simply that while the prayers mix three traditions (the Ars notoria, Liber visionum and common prayers), the crystallomantic formulae inserted in the prayers integrate at least two different sets of terminology: on the one hand, that of the actual practice of divination by means of a crystal, as represented by the Mecklenburg mirror, and on the other, that of magical circles used for the invocation of angels – a practice similar to what is described in the Clavicula – where entering and magnifying by angels makes more sense than in the case of a crystal. Both in the procedures with the help of a crystal and in those involving magic circles, there are divine names written on the object, but while the metal frames of the crystal which survived in Germany may more easily rationalize why our one is "quadrangular", the tradition of the Solomonic circles may better explain the circular form depicted on the pictures, as well as the strange terminology of the text.
 Acknowledgements: My research was sponsored by the Norddeutsche Landesbank Warburg-Wolfenbüttel Fellowship (2001-2002) and by the Central European University (Budapest), and this article was written with the support of the Hungarian Academy of Sciences (History and Philosophy of Science Research Group, Department of Philosophy and History of Science, Technical University, Budapest). As far as the intellectual support is concerned, I owe enormous debts to Milena Bartlová, W. L. Braekman, Charles Burnett, Claire Fanger, Richard Kieckhefer, Gábor Klaniczay and György Endre Szönyi for their helpful advice.
 The most comprehensive and reliable work on medieval crystallomancy and catoptromancy - in spite of its title and its date of publication - is still: Delatte, La Catoptromancie grecque. On this topic, see also Braekman, Middeleeuwse witte en zwarte magie, 437-440; and Kittredge, Witchcraft, 185-205.
 Natural magic may be defined as an art operating through the secret correspondences of the world and the hidden but natural virtues of its objects.
 The objective of divination is to foretell future events hidden but foreordained by God through the interpretation of signs.
 William of Auvergne, De universo II 3 20 and 21, 1053bC, 1054aH, 1057bC in Auvergne, Opera Omnia. See also Marrone, 'William of Auvergne on Magic', specially 745-747, as well as Delatte, La Catoptromancie grecque, 28-40.
 Eymeric, Directorium inquisitorum, 338, quoted and translated by Bailey, 'From Sorcery to Witchcraft', 973.
 Hartlieb, Das Buch aller verboten Künste. The basic secondary literature on Hartlieb is Fürbeth, Johannes Hartlieb.
 Kieckhefer, Forbidden Rites, 107 and 244-245. To these examples one can add five experiments with mirrors (called the Mirror of Floron, and that of Lilith) presented by the same source, because mirrors function in the same way for similar purposes, with the involvement of angels and virgin boys. Ibid., 104-106.
 The endurance of these traditions is well demonstrated by an interesting seventeenth-century book written in Hungarian on ritual magic, which contains instructions on how to find treasure, money, and precious stones hidden under the earth with the help of prayers and invocations. Summoning the appropriate angels and archangels (a different one for each day), the operator is to turn to the sun, to give a mirror or a crystal to a virgin boy or girl, and to iterate (flexis genibus, as usual) a long list of prayers and a set of divine names (Agios + Otheos + yschiros + Athanatos + Eleyzon + Ymas + Szentczeges Isten). His objectives extend beyond the simple wish to find treasure; he wants the angels to satisfy all his wishes and requests, provided - the text hastens to stress - that his goals are not of a malign nature, vain or indecent. See Herner and Szörényi, 'A Tudás Könyve' [The Book of Knowledge].
 See Kieckhefer, Forbidden Rites, 112-113, 140-142, 240-242, 244, 246-254 and 329-339.
 For these and many further examples for the use of virgin boys in magical rituals, see Veenstra, 'The Confession of Master Jehan de Bar', especially 352, n. 3; and Kieckhefer, Forbidden Rites, 98 and 107.
 See also Delatte, La Catoptromancie grecque, 15-18.
 From the vast literature, I just quote two important titles: Veenstra, 'The Confession of Master Jehan de Bar', and Boudet, 'Les condamnations de la magie'.
 Note that Jean de Bar's case exceeds the importance of a simple source of crystallomancy. Bar's position in the complicated context of the French royal court, and the structural and thematic correspondence of his confession with the 1398 list of articles on condemned magical arts issued by the Faculty of Theology of the University of Paris, and with Jean Gerson's De erroribus circa artem magicam is accurately examined in both Veenstra's and Boudet's articles (see the previous footnote), who discovered the textual parallel simultaneously.
 For the background of this case, see Raine, 'Divination in the Fifteenth Century'.
[16 MS Rawlinson liturg. d. 6. Its number in the Summary Catalogue is 15857; see Madan, A Summary Catalogue, 521. See also Pächt, Illuminated Manuscripts, 175, and Csapodi and Csapodi-Gárdonyi, Bibliotheca Hungarica, no. 2336. In Hungary, the manuscript may be read in a microfilm copy: Magyar Tudományos Akadémia Könyvtára, Mf. 5119/IV.
 For a published edition of the Latin text and a detailed analysis in Polish, see Bernacki and Ganszyniec, (eds.), Modlitewnik Wladyslawa Warnenczyka [Wladislas Warnenczyk's Prayer Book]. See especially the chapter by Ganszyniec, 'O Modlitewniku Wladyslawa' [On Wladislas' Prayer Book], 25-93, and that by Korzeniowski, 'Modlitewnik Warnenczyka' [Warnenczyk's Prayer Book], 13-25.
 For a description of the content of this and the other Jagiellonian prayer books, see Borkowska, Królewskie modlitewniki [Royal Prayer Books], especially 64-76.
 The emphasis on the unworthiness of the operator is a usual motif in ritual magic. See Kieckhefer, Forbidden Rites, 264: '...ita quod me famulum tuum, N., licet indignum...'
 Bernacki and Ganszyniec, (eds.), Modlitewnik Wladyslawa Warnenczyka, 68.
 Ibid., 16.
 Ibid., 17.
 Ibid., 21.
 Ibid., 16-17.
 Ibid., 42.
 Ibid., 42.
 Ibid., 15.
 Ganszyniec, 'O Modlitewniku Wladyslawa', especially 52-67. I am very grateful to Jolanta Szpilewska, (Ph.D. in 2003, Medieval Studies Department, Budapest) for letting me consult her unpublished translation of Ganszyniec's introduction.
 Bernacki and Ganszyniec, (eds.), Modlitewnik Wladyslawa Warnenczyka, 13-16. From the growing literature on the Ars notoria, I only refer here to the following: Dupebe, L' Ars Notoria; the articles in Fanger, (ed.), Conjuring Spirits; Boudet, 'L'Ars notoria au Moyen Age'; and Julien Véronese's as yet unpublished "Mémoire de DEA", entitled L'Ars notoria: une tradition théurgico-magique au Moyen Age (XIIe-XVIe siecle).
 Agrippa, Opera Omnia, vol. 2, 603-660, especially 657-659.
 Bernacki and Ganszyniec, (eds.), Modlitewnik Wladyslawa Warnenczyka, 17. This short prayer, not identified by Ganszyniec, was found by Claire Fanger, who kindly drew my attention to it.
 Agrippa, Opera omnia, 605.
 It may be added that Ganszyniec' impression on the text was the following: when including magical elements in the handbook, the compiler made magic the least explicit possible. He omitted the obviously forbidden elements, the methods of suffumigations and the most explicit rubrics of magic, since they were condemned by medieval penitential books as vane superstitiones. Thus, the compiler constructed the appearance of a regular prayer book, making use at the same time of the ritual character of this genre. As a result of this cautious balance, the magic contained in the book was invisible to everybody except the compiler. See Ganszyniec, 'O Modlitewniku Wladyslawa', 78-82. Although this conclusion seems to be outdated, since scholarship has established the category of ritual magic and since it has been exploring the purifying methods of John of Morigny, Ganszyniec was certainly right in identifying a conscious program of reinterpreting magical texts in a Christian framework.
 Borkowska, Królewskie modlitewniki, 346.
 Viard, Les Grandes Chroniques, vol. 9, 23-24.
 See, inter alia, Barnay, 'La mariophanie au regard de Jean de Morigny', and the published version of Barnay's doctoral thesis: Le ciel sur la terre. See, furthermore, the following: Watson, 'John the Monk's Book of Visions'; Fanger, 'Plundering the Egyptian Treasure'; Kieckhefer, 'The Devil's Contemplatives'.
 Fanger and Watson, 'The Prologue to John of Morigny's Liber Visionum'.
 So far only a short note has been published on this finding: Fanger and Láng, 'John of Morigny's Liber visionum and a Royal Prayer Book from Poland'. The discovery (that the author of the Polish prayer book borrowed a considerable number of prayers from the Liber visionum) was made by Claire Fanger, thanks also to my involvement: inspired by my description on the prayer book, she identified many of the prayers with excerpts in her as yet unpublished transcription of Brother John's text.
 Ganszyniec, 'O Modlitewniku Wladyslawa', 62.
 Borkowska, Królewskie modlitewniki, 74-76.
 Bernacki and Ganszyniec, (eds.), Modlitewnik Wladyslawa Warnenczyka, 18.
 Ibid., 28 and 30, see also 29, 32.
 Ibid., 59-60.
 Ibid., 59.
 Ibid., 18-19.
 Fanger and Láng, 'Liber visionum and a Royal Prayer Book', 2.
 Bernacki and Ganszyniec, (eds.), Modlitewnik Wladyslawa Warnenczyka, 59, see also ibid., 62, 64, 66.
 Ibid., 34: 'Liber iste cum summa diligencia recta disposicione, debitis diebus, horis et noctibus, vigiliis, ieiuniis, oracionibus specialibus, summa reverencia et omnibus cerimoniis (sic) scriptus, factus et compositus est'.
 Kieckhefer, Forbidden Rites, 257-259.
 The number 811 in the earlier publication of the text was based on a 16th-century English translation (British Library MS Royal 17-A-XVII), the Latin Versions give 89 (British Library MSS Sloane 3854 and 3885) and 8 (MS Sloane 313). See Hedegĺrd, Liber iuratus Honorii, 26.
 On this curious text, see Boudet, 'Magie théurgique'; and Mathiesen, 'A Thirteenth-Century Ritual'.
 Bernacki and Ganszyniec, (eds.), Modlitewnik Wladyslawa Warnenczyka, 16-18.
 Bernacki and Ganszyniec, (eds.), Modlitewnik Wladyslawa Warnenczyka, 17: 'Manifesta michi secreta quecunque voluero in hoc Cristallo, ut in illo videre valeam, per hec sancta nomina tua, quorum efficacia celum et terra et omnia que in eis sunt, contremiscunt Agla, Sabaoth, Tetragrammaton, Emanuel, Messias'. See also 'ut in cristallus sit illuminatus per sacros angelos tuos et per vim et virtutem illorum verborum essenciam divinam attinencium', ibid., 21, and 'ut tu cristallus sis illuminatus per sanctos angelos, per virtutem et vim illorum verborum', ibid., 23.
 See Kieckhefer, Forbidden Rites, 139 and 261.
 Bernacki and Ganszyniec, (eds.), Modlitewnik Wladyslawa Warnenczyka, 1.
 For a short note and three drawings on this object, see Braekman, 'A Unique Magical Mirror'.
 Bernacki and Ganszyniec, (eds.), Modlitewnik Wladyslawa Warnenczyka, 60: 'Vos ad presentis Cristalli compositionem et illustracionem invito et voco'.
 Ibid., 31: 'Ut in illo Cristallo per sanctos angelos tuos illuminatum et preparatum...' See also ibid., 35.
 Ibid., 61. For dilatare, see also 21, 38, 40.
 Ibid., 42: 'Mitte michi sanctos angelos tuos ad huius cristalli clarificacionem et illuminacionem'; 'ut omnia huius mundi secretissima secreta sub quatuor elementis contenta (...) et precipue illam rem quam pronunc scire voluero, sine omni fallacia et lesione corporis et anime (...) per sanctos angelos tuos michi manifesta erunt'. See also 22, 23, 26, 27, 43.
 Ibid., 42, see also 20, 21.
 Ibid., 21-22.
 Ibid., 23.
 Ibid., 22: '...in illo Cristallo per sanctos angelos tuos consecrato'.
 For analogies of entering and illuminating a crystal, taken from a famous magical manuscript (Bodleian Library, MS Rawlinson D 252), see Delatte, La Catoptromancie grecque, 102-103.
 The miniatures are reproduced at the end of Bernacki and Ganszyniec, (eds.), Modlitewnik Wladyslawa Warnenczyka.
 For a not very reliable English translation of the text, see Mathers, The Key of Solomon the King. The same can be found on the following website: http://www.esotericarchives.com/solomon/ksol.htm
 Circle from MS London British Library Kings 288, p. 21.
 British Library, add. Ms 10862, f. 12v.
 British Library, add Ms 10862, f. 14v.
 Boudet, 'Magie théurgique', 869.
 A text with the title Clavicula Salomonis is mentioned for example in the fifteenth-century book list of the Milan dukes (Pellegrin, La Bibliotheque des Visconti et Sforza, 322). This should be taken, however, with certain caution, since it is possible that similar titles refer to a different texts, or to different versions of the Clavicula.