[In the following essay, Kibre focuses on Albert's association with the Medieval science of alchemy and on several apocryphal alchemical texts sometimes attributed to him.]

Albert's interest in alchemy, the art, in his words, that best imitates nature, is revealed in the references to the subject in his authentic writings, particularly the Book of Minerals (Liber mineralium), his Commentary on Aristotle's Meteorology, and other tracts. He had investigated and made a careful study of the subject in the course of his inquiry into the nature of metals, for guidance in which he had sought in vain for the treatise by Aristotle. Without that guide, he was, as he reported, obliged to follow his own devices and to set down what he had learned from philosophers or from his own observations. He had thus at one time become a wanderer, journeying to mining districts to "learn by observation the nature of metals." "And," he stated, "for the same reason I have inquired into the transmutations of metals in alchemy, so as to learn from this, too, something of their nature and accidental properties." Among the names of the philosophers to whom Albert had turned were some of the principal authorities on alchemy, current in the twelfth and thirteenth centuries in Latin translation from the Arabic, comprising chiefly Hermes, Callisthenes (that is Khālid ibn Yazid), Democritus, Gigil, and Avicenna. Of these Albert relied principally upon Avicenna (Abū;All̄i Sināa, 980-1037), utilizing both the apocryphal and authentic tracts appearing under his name. Albert thus cited a section of the supposititious Avicenna tract On the Soul in the Art of Alchemy (De anima in arte alchemiae), one of the most influential of the alchemical tracts upholding the possibility of the transmutation of metals. Naming the work, "The Physical [Stone]," Albert referred only to the final section, the "Exposition of the physical stone by Avicenna to his son Aboali (Abū Ali)," which circulated as a separate tract. In addition, Albert utilized the so-called "Letter of Avicenna to King Hasen (or Hazen), the philosopher," in which is set forth the view commonly held in the thirteenth century, that quick-silver (mercury or argentum vivum) and sulphur are the materials of all metals and hence basic to the alchemical process. This so-called newer theory of the components of metals, Albert contrasted with the older view expressed by Aristotle, that metals are formed from a subtle fatty moisture (humidum unctuosm subtile) combined with a subtle earthy tincture.

In addition, in his search for "immediate efficient causes existing in the material and transmuting it," Albert continued his critical evaluation of so-called authori-ties and the operations of alchemy. He characterized as erroneous the opinions of Hermes, Empedocles, Democritus, "and some of those in our own time who are practitioners of alchemy," and who are concerned with the generation of stones. These authorities mistakenly suggested, he reported, that all stones are produced by accident without a specific cause for their production, whereas the true or productive cause, Albert asserted, is a "mineralizing power." The making of stones, he concluded, by the operations of the alchemists is even more difficult than the making of metals. Albert had earlier noted that just as metals are formed from water congealed by intense cold and dryness, just so is the work of the alchemists performed, that is by separating and sublimating the humidity of iron. Moreover, in the operations of alchemy, he noted that mercury (argentum vivum or quicksilver) that is dried by much burning and mixture with sulphur will be coagulated by heating in a furnace with green wood.

Albert next went on to draw attention to the discussions unfavorable to the transmutation of metals which he attributed also to Avicenna, wrongly citing the "Letter to King Hasen" as the source rather than Avicenna's tract on minerals, De congelatione et conglutinatione lapidum. In this treatise which has been shown to be an excerpt from the authentic book Book of the Healing of the Soul (Kitāb al-shifa'), Avicenna disparaged the "claims of the alchemists" whose "power to bring about any true change of metallic species," he denied with the words, "Let practitioners of alchemy know that they cannot transmute one form of metal into another, but only make something similar… As to the rest, that is that specific differences between metals may be removed by some clever method, I [Avicenna] do not believe… possible". Albert went on also to paraphrase Avicenna's further statement (in the "Letter to King Hasen on Alchemy") that he had examined the books of those upholding "the art of transmutation" and had found them devoid of the reasoning that belongs to every art. He had found most of their content nonsensical. Moreover, an examination of the books of those who opposed the art of transmutation revealed that their arguments and reasoning were too feeble and trivial to destroy belief in the art. Hence it appeared prudent to add that "specific forms are not transmuted, unless perhaps they are first reduced to prime matter (materia prima) … and then, with the help of art, developed into the specific form of the metal" desired. Albert then added to Avicenna's stricture his own criticism of the alchemical literature: "I have examined many alchemical books, and I have found them lacking in [evidence] and proof." They merely rely "on authorities," and conceal "their meaning in metaphorical language, which has never been the custom in philosophy. Avicenna is the only one who seems to approach a rational [attempt], though a meagre one, towards the solution of the above question, enlightening us a little."

Albert, moreover, was critical of opinions expressed by alchemists which did not coincide with those of Aristotle or Avicenna. He cited the undeniable but nonspecific statement that metals are made up of all the elements, expounded in the Book of Alchemy, by Hermes, the mythical or legendary founder of alchemy, who was probably of Greek origin but was known to the west through Latin translations from the Arabic. Albert also characterized as "the strangest and most ridiculous of all opinions, the one that held that 'calx (quicklime) and lixivium (lye) are the material of all metals'," an opinion he attributed to Democritus. Albert asserted that this statement about the material of metals does not fit the fact, and is incorrect. He further referred to the opinion "that alchemy is the science that confers upon inferior metals the nobility of the superior ones," expressed by Callisthenes; and to the attempt "to prove that fused ash is the material of metals," reported in the book of Secrets by "Gigil of Moorish Seville," which Albert noted, "has now been returned to the Spaniards." Albert went on to characterize Gigil's arguments in defense of his assertion as "unconvincing and stupid," and "Gigil himself as "a mechanic and not a philosopher" who relied too greatly upon "the mechanical operations of alchemy" and was guilty of making incorrect assertions regarding natural science.

Albert next drew attention to the procedures and objectives of the alchemists. "The experience of the alchemists," he asserted, "confronts us with two grave doubts. For they seem to say that the specific form of gold is the sole form of metals and that every other metal is incomplete—that is, it is on the way toward the specific form of gold, just as anything incomplete is on the way toward perfection." Thus metals lacking the form of gold in their material "must be diseased." Hence to cure or remove these diseases the alchemists endeavor "to find a medicine which they call the elixir, by means of which they may remove the diseases of metals . . ." and bring "out the specific form of gold." Continuing further with the use of the elixir and the transmutation of metals, Albert asserted that since "it is found by experience that by means of the elixir copper turns to silver, and lead to gold, and iron likewise to silver," the alchemists erroneously conclude "that the specific form of all metals is one and the same, but the diseases of the material are many," an opinion with which Albert would not concur. He went on rather to discuss the means, that is the use by the alchemists of "calcination, sublimation, distillation, and other operations," to induce the elixir to penetrate into the material of metals, and hence possibly "to destroy the specific forms of metals that originally were in the material The material that remains can then with the help of the alchemical art be reduced to another specific form, just as seeds are helped by ploughing and sowing or [as] nature is helped by the efforts of the physician." This explanation, Albert noted, was not acceptable to "Hermes and Gigil, and Empedocles and almost all that group of alchemists," who appeared to defend the "stranger" principle "that in any metal whatever there are several specific forms and natures, including one that is occult and one that is manifest." Albert himself had earlier expressed his opinion that in the case of the "experiments which the alchemists bring forward," to establish the validity of their conclusions, they do not offer enough proof.

Albert then went on further to compare the procedure of the skillful alchemists with that of the skillful physicians, and also to enlarge upon his theory of nature's role. The skillful physicians, he asserted, "by means of cleansing remedies clear out the corrupt or easily corruptible matter that is preventing good health—the end which physicians have in mind. In doing so, they strengthen and aid the power of nature, directing it to bringing about natural health. [Good] health will [thus] be produced by nature, as the efficient cause; and also by art as the means and instrument." The skillful alchemists also proceed similarly in transmuting metals. They first cleanse thoroughly the mercury or quicksilver and sulphur, the constituents of metals; then, when this is done, "they strengthen the elemental and celestial powers in the material, according to the proportions of the mixture in the metal that they intend to produce." Thus "nature itself performs the work, and not art, except as the instrument, aiding and hastening the process." "The alchemists appear, in this manner, to produce and make real gold and real silver, since the elemental and celestial powers can produce in artificial vessels, if they are formed like those in nature, whatever they produce in natural vessels. Hence "whatever nature produces by the heat of the sun and stars, art also produces by the heat of fire, provided the fire is tempered so as not to be stronger than the selfmoving formative power in the metals." The inclusion of the "stars" as an agency influencing chemical operations is further exemplified in Albert's assertion in his De causis elementorum that "when skilled alchemists work during the waxing of the moon, they produce purer metals and stones." Albert also referred to the introduction by Hermes of the association of the seven planets with the seven metals so that the substitution of the names of the planets for the metals, such as sol for gold, luna for silver, and so on, became common practice. In general, Albert noted, "of all the operations of alchemy, the best is that which begins in the same way as nature," that is "with the cleansing of sulphur by boiling and sublimation, and the cleansing of quicksilver, and the thorough mixing of these with the material of metal; for in these by their powers, the specific form of every metal is induced." Moreover, the alchemist proceeds by destroying "one substance by removing its specific form, and with the help of what is in the material producing the specific form of another [substance]."

Although Albert recognized in the above directions the theoretical validity of the alchemical process he was obliged to admit that he had never seen it successfully carried to completion. He thus stated that "we have rarely or never found an alchemist, as we have said, who [could] perform the whole [process]." It is true that "One of them may indeed produce with the yellow elixir the color of gold," and with "the white elixir, a color similar to silver"; and "may endeavor to make the color remain fast when it is placed in the fire and has penetrated the entire metal just as a spiritual substance is put into the material of a medicine." He may by this operation induce a yellow color, while at the same time "leaving the substance of the metal unchanged." Such operators Albert denounced as "deceivers." Without doubt they are deceivers… since they do not make real gold and real silver." And yet most alchemists follow this practice in whole or in part. "For this reason I have had tests made on some alchemical gold, and likewise silver, that came into my possession, and it endured six or seven firings, but then, all at once, on further firing, it was consumed and lost and reduced to a sort of dross."

In accord, moreover, with his view that the aim of a natural scientist is not merely to accept the statements of others, but rather to make an effort to observe the phenomena at first hand, Albert supplemented the knowledge of alchemy that he had derived from past authorities in his reading of books on medicine and alchemy, with the results of his own observations and experiences. From his visits to mining districts, metal workshops, and alchemical laboratories, he had acquired a practical acquaintance with the nature of metals by a direct observation of processes in nature. "I have learned," he explained, "by what I have seen with my own eyes, that a vein flowing from a single source was in one part pure gold, and in another silver…" And "[from what] miners and smeltermen have told me …[that] what artisans have learned by experience is also the practice of alchemists who, if they work with nature, transform the specific form of one metal into another." Furthermore, from visits to laboratories, in all probability in Cologne and Paris, Albert reported on the results of his inquiries into "the transmutation of metals in the art called alchemy" which he had directed to contemporary workers in the field, that is the "alchemists of our time," whose names he does not reveal. He referred to alchemical experiments which showed that watery moisture is easily converted into vapour, and to the use of the alembic. He noted that minerals that seem to be intermediate between stones and metals are important reagents in alchemy since they may be influenced by laboratory treatment. And he added, "On these substances depends most of the science of those who endeavor to convert one [metal] into another." He had further reported on operations similar to those of the alchemists, such as drying of mercury by frequent burning and mixture with sulphur or when placed in a hot furnace with green wood," or of the forming of metals "from water congealed by intense coldness and dryness." And he also went on to note in his exposition of the alchemical art, which as earlier noted he had termed the best imitator of nature, that of the two major constituents, sulphur is known as the father and quicksilver as the mother, "as the writers on alchemy metaphorically" suggest. Moreover, he drew attention to the fact that since in alchemy there is no better way of proceeding than with the yellow elixir made with sulphur, the alchemists have observed that there is an unctuousness in sulphur so intensely active in burning that it burns all metals, and in burning blackens everything on which it is cast. Hence, the alchemists recommend that the sulphur be washed in acid solutions and that it be cooked until no more yellow liquid comes forth. These solutions may then be sublimed until all the unctuousness capable of burning has been removed, and there remains only as much subtle unctuousness as can endure the fire without being reduced to ash. This is, Albert added, "expressly stated by the authorities, Avicenna, Hermes and many others, who are men of great experience in the nature of metals." Albert had also noted unskilled alchemists at work in the digestion or boiling by moist heat of the earthiness in the moisture in metals.

The foregoing details regarding Albert's concern with alchemy provide convincing evidence of his interest in the subject. They also demonstrate Albert's belief in the possibility of the transmutation of metals, although he judged the process to be very difficult and beset with the errors and imitations of imposters. "For [as quoted by Partington] alchemical gold does not gladden the heart like the real gold, and is more [easily] consumed by fire, yet transformation may really be produced by exspoliation of properties by alchemical operations, as Avicenna teaches." Albert's desire to explore the entire matter of the possible transmutation of metals as thoroughly as possible is further exemplified by his study of the principal authorities and direct observation of alchemical procedures in laboratories as well as by association with contemporary alchemists whose names he does not provide. However, there appears to be a dearth of contemporary evidence to attest that Albert himself was considered an adept alchemist or that he engaged in or performed the al-chemical processes he describes. He appears rather to have been an acute observer, an onlooker, but not an active participant in the laboratory experiments.

Despite the lack of contemporary and specific evidence of Albert's direct participation in alchemical laboratory procedures, his fame and repute as a skilled alchemist became manifest not long after his death. By the mid-fourteenth century he is mentioned in catalogues as author of an alchemical tract and is credited with having had as a disciple in this art, Roger Bacon, the English schoolman. Nor did this repute diminish in the fifteenth and sixteenth centuries. In a collection of Stowe manuscripts, Hugh of England named Albert as one of the several authorities in the field. This fame, whether deserved or not, appears to have motivated the attachment to Albert's name of some twenty-eight or more tracts on alchemy. They appear in manuscripts dating from the close of the thirteenth century with the major number in the late fourteenth or fifteenth century. How much of this literary output can be attributed to the common practice in the Middle Ages of attaching to such treatises the names of prominent churchmen in order to give them respectability and insure their acceptance cannot be determined. Nor does the explanation that Albert was confused with a chemist who lived at Cologne, provided by Naude in his "Apology for all Great Personages Who Have Been Falsely Suspected of Magic," seem adequate. What does appear clear is the fact that for the most part the alchemical tracts bearing Albert's name as author reflect, in keeping with Albert's authentic writings, an active interest in not only the philosophical bases of the alchemical art but also in its practical and experimental aspects.

The individual alchemical treatises that appeared under Albert's name have elsewhere been enumerated and analyzed briefly together with the manuscripts and printed editions in which they are found. Hence it will perhaps suffice here merely to draw attention first to some general characteristics of the tracts and second, to choose some examples for more specific comparison with the information contained in Albert's authentic works. In general the treatises are free from the mystifying and allegorical features upon which Albert himself in theBook of Minerals had cast aspersion as characteristic of alchemical tracts. In this respect the imprint of Albert's didactic method, noteworthy for clarity of expression and systematic arrangement, was strong enough to influence those who professed to write under his name. As in Albert's exposition to his confreres of the Aristotelian scientific corpus, the professed purpose of the authors of the alchemical tracts, in the majority of cases, was to explain to their readers in as simplified a fashion as was necessary for their understanding, the art of alchemy, its theory and practice.

The above features are exemplified specifically in the Little Book of Alchemy (Libellus de alchimia or Semita recta), the tract most consistently attributed to Albert and extant in manuscripts dating from the close of the thirteenth century. The clear, concise, and well ordered account of alchemy contained in this tract resembles Albert's treatment of other topics of natural science in his authentic works. It also provides an excellent introduction to the alchemical art of the late thirteenth and fourteenth centuries. The author is particularly concerned with making known to his confreres, the aims, accoutrements and processes of alchemists and the alchemical art. His instructions are detailed and even repetitious in character. They are, moreover, together with the frequent cautions and admonitions, largely practical in nature. Yet, true to the professed author's ecclesiastical calling, the work opens with the phrase from Ecclesiasticus: "All wisdom is from the Lord God." However, despite the fact that the suggestions contained in the tract are largely practical in nature and might perhaps have emanated from Albert, the author's style, beginning with the introduction, differs pointedly from that of Albert in his authentic works.

For example, the introductory phrases contain the author's stated conviction that he has found what he was seeking; not, however, (in his words) "by my own knowledge, but by the grace of the Holy Spirit. Therefore, since I discerned and understood what was beyond nature, I began to watch more diligently in decoctions and sublimations, in solutions and distillations, in cerations and calcinations and coagulations of alchemy and in many other labors until I found possible the transmutation into gold and silver, which is better than the natural [metal] in every testing and malleation." This does not coincide with Albert's view in theBook of Minerals. There he had expressed his belief that while the transmutation of baser metals into gold was theoretically possible, it had not so far been accomplished by the alchemists; also that while the alchemists were able to produce a metal similar to gold, their product was inferior to natural gold or silver and did not stand the accepted test for gold. Moreover, while the author of the Little Book of Alchemy looked "beyond nature," Albert had repeatedly stipulated that the observation of nature and natural processes provided the best guide.

Yet despite these essential differences it appears evident that the author of the Little Book of Alchemy was acquainted with Albert's work, or at least utilized similar sources. He repeated from Avicenna's Congelatio the phrase which he mistakenly attributed to Aristotle, "Let the masters of alchemy know that the species of things cannot be changed," and the accompanying statement, here also attributed to Aristotle, "I do not believe that metals can be transmuted unless they are reduced to prime matter, that is purified of their own corruption by roasting in the fire." Only then is trans-mutation possible.

The treatise itself also has some interesting features. Among these are the enumeration of possible errors and the list of specific precepts to guide those undertaking the enterprise. For example, attention is drawn to the fact that some were incapable of carrying out certain sublimations "because they failed to grasp the fundamentals"; "others because they used porous vessels." Also, in the precepts, the first provided that "the worker in this art must be silent and secretive and reveal his secret to no one"; and the eighth "that no one should begin operations without plenty of funds … for if he should … Jack funds for expenses then he will lose the material and everything." Contributing further to the practical nature of the tract are the descriptions of the various utensils, furnaces, ovens, and flasks; then the spirits: quicksilver, sulphur, orpiment, and sal ammoniac; and finally the elixir or fermentum, the medicine or philosophers' stone capable of transmuting baser metals into gold and silver.

Another even more practical tract, the Alkimia minor, is attributed in the manuscripts to "Brother Albert of Cologne of the Order of Preaching Friars." Best described, perhaps, as a laboratory manual, it has directions for the preparation of chemical substances, for the dyeing of metals red or white, that is the transmutation into gold or silver, and for the preparation of the elixir or medicine, the transmuting agent. Like the Little Book of Alchemy or Semita recta, of which it seems to include abstracts, the Alkimia minor appears to have been in circulation by the mid-fourteenth century, although no manuscripts of the text earlier than the fifteenth century have been located so far. However, the tract is listed with the same opening words among the books contained in a collection of alchemical treatises of the early fourteenth century. The text itself gives no indication of the date of composition, although the chemical knowledge coincides with that of similar writings of the thirteenth and fourteenth centuries. The tract provides details of laboratory procedure and of apparatus and utensils. The directions are simple and straightforward with no attempt to mystify. Yet, the work does conform to the common practice of assigning names of planets to the minerals, and it also makes use of the term medicine as a synonym for elixir, the transmuting agent. Similarly, the use of "to redden" (ad rubeum) or "to whiten" (ad album) for the gold or silver making recipes can be found. An explanation for the use of these terms is given in the Book of Minerals. Many of the chemical substances utilized were already described in such works as the Book of Minerals and the Little Book of Alchemy. In general, the Alkimia minor is characterized by a total lack of attention to theory; the emphasis is on actual procedure and practice. Many of the processes listed, such as sublimation and distillation, for example, are common to pharmacy as well; and there is great variety in the laboratory apparatus. Included were furnaces, the baker's oven (furnus panis), and the furnace of reverberation, the dung bath, marble slab, alembics, aludel, recipient (ampulla,) and various kinds of jars, flasks, and vessels; earthen, copper, and glass, closed or open; a descensory, that is a vessel or retort used in distillation by descent, and pestles of iron or wood, as well as a mallet or hammer.

A further tract attributed to Albertus Magnus for which there are no fourteenth-century manuscripts extant but which is named in the same fourteenth-century alchemical miscellany as the Alkimia minor, is that entitled "On the hidden things of Nature" (De occultis naturae.) This treatise provides a survey of the various alchemical doctrines set forth by alchemical authorities chiefly of Arabic origin. The work bears only a slight resemblance to the other alchemical tracts ascribed to Albertus Magnus. It professes to have been written in response to a request by a reverend father, addressed in the course of the work. Unlike either the Semita recta or the Alkimia minor, with which it is frequently found in the manuscripts, the De occultis naturae relates more to the theoretical side of alchemy than to the practical although both aspects are covered. The author has utilized a large number of writers with the intention, he informs us, of making it unnecessary for the reader to consult them further since their principal doctrines will have been transferred in briefer form to the present compendium. In general the treatise ap-pears to resemble more the alchemical writings of the fourteenth rather than those of the thirteenth century in its predilection for alchemical jargon, allegorical devices, and mystical phraseology.

Of the remaining alchemical treatises appearing under Albert's name, it may suffice to note here two further examples. The tract On Alchemy (De alchimia) which appears not to have been available before the fifteenth century, bears a close relationship with the Book of Minerals in several of the arguments presented and in the discussion regarding alchemy. It is distinguishable from the Little Book on Alchemy (Libellus de alchimia or Semita recta) by the opening words: "Callisthenes one of the earlier founders of our art after Hermes…" In addition to Callisthenes, the author names other authorities similar to those included in Albert's discussion in the Book of Minerals, such as Hermes, and Avicenna. In addition he names Geber Hispanus instead of Gigil and attributes to him the statement with some verbal changes, that Albert expresses as his own, in the Book of Minerals, namely that he has examined certain alchemical books and has found them to be without distinction and with their intention hidden under the guise of allegory. The author here also follows the current practice of using the names of the seven planets as synonyms for the metals, a practice that Albert attributed to Hermes. But he fails to repeat here the references to the influence of the heavens in the alchemical process found in the Book of Minerals.. On the other hand he follows Albert's emphasis upon the principle that alchemy imitates nature and hence that it is necessary to observe carefully and closely natural processes.

The other tract attributed to Albert that we would note here, namely the Compound of Compounds (Compositum de compositis) attracted attention in the fifteenth to seventeenth centuries when it was translated into French and English. However, the text in the late manuscripts resembles closely that found without Albert's name as author in a fourteenth-century manuscript at Edinburgh. In that text the work is said to have been collected and promulgated by masters at Paris in the year 1331. However, in the later manuscripts at Paris and the Vatican it is clearly attributed to Albertus Magnus. In the course of the work reference is made to "our Book on Minerals" which is suggestive of Albert. There are included in the tract discussions on the theory of alchemy along with practical recipes for the preparation of vermillion and of white sublimate.

Of the remaining alchemical treatises appearing under Albert's name, none, with the exception of those that are also ascribed to other authors as well, appeared before the fifteenth century. Although the relation of these alchemical texts to Albert is tenuous to say the least, they do attest to his repute as an adept alchemist in the decades and centuries following his death.