(Theophilus Presbyter , also called Rugerus
(fl. Helmarshausen, Germany [?], early twelfth century),
The pseudonmyous author of De diversis artibus, an instructive treatise on practical arts for the adornment of the church, Theophilus wrote in the first quarter of the twelfth century–perhaps, as Lynn White has suggested, in 1122–1123 in answer to Bernard of Clairvaux’s animadversions on ecclesiastical luxury. On the basis of a note “qui et Rugerus,” written in the seventeenth century on the title page of the Vienna manuscript, Albert IIg identified Theosphilus with the Benedictine monk Roger, who was active as a goldsmith in Helmarshausen around 1100 and slightly after. Although this identification was not accepted by two subsequent editors, Degering and Theobald, the most recent studies support it. Helmarshausen was an important center in northwestern Germany for all of the arts described by Theophilus, and some surviving pieces of ecclesiastical metalwork made by the historic Roger are of a style that almost seems designed to illustrate the metalworking techniques described in the manuscript.
The work is often called Diversarum artium schedula, following Lessing, who adopted a pharse from the preface to book I in two manuscripts that lacked titles. The title De diversis artibus was found by Dodwell on both the Vienna and the Cambridge manuscripts, and has been used by him and subsequent writers.
There are three parts to the work – book I, on the art of the painter; and book II, on the art of the worker in glass; and book III, on the art of the metalworker. The last is most detailed. Art historians have made much use of book I; but the sections on glass and metalwork are of more importance in the history of science and technology, for they constitute the earliest firsthand accounts of many pyrotechnological processes that later bore fruit in chemical science and engineering, as well as in the entire modern materials industry.
With no theoretical speculation whatever, Theophilus recorded intimate practical details of the preparation of pigments, dyes, stained glass, brass, and bronze; the alloying and working of gold and silver; the heat treatment of steel; and the casting of metal objects ranging from small silver chalice handles made by the lost-wax process to huge bronze bells cast in clay molds shaped on a lathe. He described the separation of gold and silver by cementation and by sulfide reaction, as well as the removal of impurities by cupellation. His solder compositions were close to the minimum-meltingpoint alloys in the series copper-silver and lead-tin as known today. Theophilus gave details for the manufacture on a fairly large scale, for use as pigments, of mercury sulfide, basic copper acetate (verdigris), lead oxides (both PbO and Pb3O4), and lead carbonate. Silver sulfide was made and used as niello; linseed oil appeared as a varnish; gold leaf and powder were prepared for manuscript illumination; and vegetable colors sensitive to pH were properly employed. Glass was made by melting a fritted mixture of sand and beechwood ashes in wide-mouthed pots set in a relatively large furnace with a separate fritting hearth. This is the first written reference to the use of wood ashes to produce potassium glass, which two centuries earlier had begun to replace the ancient sodium glass based on natron. The color of Theophilus’ glass changed with melting conditions and seems to have depended on the state of oxidation of iron and manganese present as impurities in the raw materials, although coloring through intentional additions of metallic oxides had been well established centuries earlier.
Mechanically, Theophilus made no use of the wind and water power sources that were just being introduced; but he described smaller devices, such as the rotary grindstone, the lathe (in several modifications), an elaborate organ, and a device for corsshatching iron surfaces to receive silver and gold overlay. He described in detail all the metalworker’s tools, including the wire-drawing plate. There is little quantitative measurement and no philosophical speculation on the nature of materials; but Theophilus admirably reflects the practical environment and the mental attitude that characterized prescientific technology, and that led to many discoveries of the properties of different kinds of substances, the effects of heat upon them, and the nature of chemical reactions in general. Theophilus was not, of course, the inventor or discoverer of the processes he records, which had existed as practical tradition–in some cases for many centuries–without being reflected in the written record. Virtually everything he says is clear and is confirmed by the evidence of surviving contemporary objects.
Theophilus was an original writer–the first to describe clearly, from personal experience, the practical arts for the purpose of instruction and inspiration. His De diversis artibus is an incomparably better source of information on medieval technology than are the compilations of ancient and corrupt recipes, such as the Mappae clavicula and the Compositiones variae and their derivatives, which were in existence at the same time and were more a product of the acquisitiveness of librarians than of the practical labors of technical men.
I. Original Works. The earliest MSS of the De diversis artibus are two of the 12th century, one at Wolfenbüttel (Herzog-August Bibliothek 4373) and one at Vienna (Nationalbibliothek 2527). The 13th-century MS in the British Museum (Harley 3915) is the most complete. For a listing of later MSS. see Johnson, Dodwell, and Hawthorne and Smith (below).
The best Latin text, with critical apparatus and English trans., is C. R. Dodwell, Theophilus, De diversis artibus . . . . Theophilus, The Various Arts . . . . (London, 1961). The first complete printed ed., based mainly on the Wolfenbüttel MS, was published by G. E. Lessing in his Zur Geschichte und Literatur aus den Schützen der herzoglichen Bibliothek zu Wolfenbüttel, VI (Brunswick, 1781), frequently repr. throughout the 19th century in Lessing’s Sämmtliche Schriften. A critical text and French trans. by Charles de l’Escalopier (Paris, 1843) was soon followed by Robert Hendrie’s text (mainly based on the British Museum MS) and English trans., Theophili, qui et Rugerus, presbyteri et monachi libri III. De diversis artibus; Seu diversarum artium schedula . . ., with a second title page, An Essay Upom Various Arts . . . bu Theophillus. Called Also Rugerus, Priest and Monk, Forming an Encyclopedia of Christian Art of the Eleventh Century (London, 1847). A frequently cited, though carelessly edited, text and German trans. is by Albert IIg: Theophilus Presbyter Schedula diversarum artium . . . . Revidierier Text, Übersetzung und Appendix, no. 7 in the series Quellenschriften für Kunstgeschichte und Kunsttechnik des Mittelalters und der Renaissance (Vienna, 1874).
All the above eds. were mainly art-historical or philological in purpose. The first to be edited primarily for its technical content was the text, and German trans., of bks. II and III by Wilhelm Theobald, Technik des Kunsthandwerks im zehnten [sic] Jahrhundert des Theophilus Presbyter Diversarum artium schedula, in auswahlneu herausgegeben, übersetzi und erläutert . . . . (Berlin, 1933). Then, after over a century of neglect in English, two independent eds. appeared whitin two years–Dodwell (see above) and J. G. Hawthorne and C. S. Smith, On Divers Arts. The Treatise of Theophilus. Translated From the Medieval Latin With Introduction and Notes (Chicago, 1963). There are several other 19th-century eds.
II. Secondary Literature. Discussions of Theophilus’ treatise and its influence are in the intro. to the printed eds. listed above. The German 1933 and English 1963 translations have extensive technical notes on glass and metalwork. For pigments, see especially H. Rosen-Runge, “Die Buchmalereirezepte des Theophilus,” in Münchner Jahrbuch der bildenden Kunst, 3rd ser., 3–4 (1952–1953), 159–171; and Farbgebung und Technik frümittelalterliche Buchmalerei. Studien zu den Traktaten Mappae Clavicula und Heraclius 2 vols. (Munich, 1967).
On the MSS and background, see Hermann Degering, “Theophilus Presbiter qui et Rugerus,” in Westfälische Studien . . . Alois Bömer gewidmet (Leipzig, 1928), 248–262; R. P. Johnson, “Note on Some Manuscripts of the Mappae Clavicula,” in Speculum, 10 (1935), 72–81; “The Manuscripts of the Schedula of Theophilus Presbyter,” ibid., 13 (1938), 86–103; and Compositiones variae . . . An Introductory Study, XXIII, no. 3 in illinois Studies in Language and Literature (Urbana, 1939); D. V. Thompson, “The Schedula of Theophilus Presbyter,” in Speculum, 7 (1932), 199–220; “Theophilus Presbyter . . .,” ibid., 42 (1967), 313–339; Lynn White, Jr., “Theophilus Redivivus,” in Technology and Culture, 5 (1964), 224–233; and C. S. Smith and J. G. Hawthorne, “Mappae Clavicula, a Little Key to the World of Medieval Techniques,” in Transactions of the American Philosophical Society, 64 pt. 4 (1974).
Cyril Stanley Smith
THEOPHILUS (Heb. Yedidiah ), high priest from 37 to 41 C.E. Theophilus, the son of Hanan son of Seth, was appointed by Vitellius, the Roman governor of Syria, in place of his brother Jonathan (Jos., Ant., 18:123) and served in that office until removed by King *Agrippa i (ibid., 19:297). Mattathias, the son of Theophilus, was high priest when the war against Rome broke out (66 C.E.).
Schuerer, Gesch, 2 (19074), 271; Klausner, Bayit Sheni, 5 (19512), 22; E. Bammel, in: ZDPV, 70 (1954), 147ff.; E.M. Smallwood, in: JTS, 13 (1962), 14–34.
One of the spirit controls of William Stainton Moses, "Theophilus" was said to be St. John the Apostle.