Take for a moment the example of the great English medieval scientist who wrote near the end of the [{134}] thirteenth century a work on science, which was undertaken at the command of the Pope of his time, to show him the character of the teaching of science at the University of Oxford. Roger Bacon defined the limits of chemistry very accurately and showed that he understood exactly what the subject and methods of investigation must be, in order that advance should be made in it. Of chemistry he speaks in his "Opus Tertium" in the following words: "There is a science which treats of the generation of things from their elements and of all inanimate things, as of the elements and liquids, simple and compound, common stones, gems and marble, gold and other metals, sulphur, salts, pigments, lapis lazuli, minium and other colors, oils, bitumen, and infinite more of which we find nothing in the books of Aristotle; nor are the natural philosophers nor any of the Latins acquainted with these things."
The thirteenth century saw the rise of a number of great physical scientists, who made observations that anticipated much more of our modern views on scientific problems than is usually thought. One of the greatest of the chemists of the thirteenth century was Albert the Great, or Albertus Magnus, as he is more familiarly called, who taught for many years at the University of Paris. He was a theologian as well as a physician and a scientist. His works have been published in twenty-one folio volumes, which will give some idea of the immense industry of the man. Those relating to chemistry are as follows: Concerning Metals and Minerals; Concerning Alchemy; A Treatise on the Secrets of Chemistry; A Brief Compend on the Origin of the Metals; A Concordance, that is, a Collection, of Observations from Many Sources, with Regard to the Philosopher's [{135}] Stone; A Treatise on Compounds; a book of eight chapters on the Philosopher's Stone. Most of these are to be found in his works under the general heading "Theatrum Chemicum." Thomson, in his "History of Chemistry," says, that they are, in general, plain and intelligible. Albertus Magnus's most famous pupil was the celebrated Thomas Aquinas. Three of his works are on chemistry: The Intimate Secrets of Alchemy; on the Essence and Substance of Minerals; and finally, later in life, the Wonders of Alchemy. It is in this last work, it is said, that the word amalgam occurs for the first time. While Thomas Aquinas and Albertus Magnus were working in France and Germany, Roger Bacon was doing work of similar nature at Oxford in England. Altogether, he has eighteen treatises on chemical problems. Some of these contain wonderful anticipations of modern chemistry. After Roger Bacon came Raymond Lully, who wrote, in all, sixteen treatises on chemical subjects. At about the same time, Arnold of Villanova was teaching medicine at Paris and paying special attention to chemistry. From him there are twenty-one treatises on chemical subjects still extant. Arnold of Villanova died on the way to visit Pope Clement V., the immediate predecessor of John, who lay sick unto death at Avignon.
It is evident, then, that there was no spirit of opposition to chemistry gradually forming itself in ecclesiastical circles, and about to be expressed in a decree by John. The chemists of the thirteenth century had been among the most distinguished churchmen of the period. One of them at least, Thomas Aquinas, had been declared a saint. Another, Albertus Magnus, has been given the title of Blessed, signifying that his life and [{136}] works are worthy of all veneration. Pope John XXII. had as a young man been a student of these men at the University of Paris, and would surely have imbibed the tradition of their interest in the physical sciences. That he should have unlearned all their lessons seems out of the question.
It remains, then, to see whether there was any diminution of the interest in chemistry after the issue of this decree by John. In the fourteenth century we find the two Hollanduses, probably father and son, whose lives run during most of the century, doing excellent work in science. They frequently refer to the writings of Arnold of Villanova, so that they certainly post-date him. From them altogether, we have some eleven treatises on various chemical subjects. Some of these, especially with regard to minerals, have very clear descriptions of processes of treatment which serve to show that their knowledge was by no means merely theoretical or acquired only from books.
Probably before the end of the fourteenth century there was born a man who must be considered the father of modern pharmaceutical chemistry. This was Basil Valentine, the German Benedictine monk, whose best known work is the "The Triumphal Chariot of Antimony." Its influence can be best appreciated from the fact that it introduced the use of antimony into medicine definitely, and that substance continued to be used for centuries, so that it was not until practically our own generation that the true limitations of its usefulness were found. Valentine described the process of making muriatic acid, which he called the spirit of salt, and taught how to obtain alcohol in concentrated form. Altogether, this monk-alchemist, who was really the [{137}] first of the chemists, left twenty-three treatises, some of them good-sized books, on various subjects in chemistry. [Footnote 18] It does not look, then, as though chemistry was much neglected during the fourteenth and fifteenth centuries.
[Footnote 18: For a brief sketch of his career see my Catholic Churchmen in Science. Dolphin Press, Philadelphia. 1906.]
One step more in the history remains to be taken, which brings us down to a man who is more familiar to modern physicians--Paracelsus. Paracelsus received his education just at the beginning of the sixteenth century, before the Reformation began. He was not a man, as those who know his character will thoroughly appreciate, to confess that he had received much assistance from others. He does mention, however, that he was helped in his chemical studies by the Abbot Trithemius, of Spanheim; by Bishop Scheit, of Stettbach; by Bishop Erhardt, of Lavanthol; by Bishop Nicholas, of Hippon; and by Bishop Matthew Schacht.
We have been able to follow, then, the development of chemistry during the fourteenth and fifteenth centuries down to the time of the Reformation, and find nowhere any lessening of the ardor for chemical studies, though most of the great names in the science continue to be, as they were before the decree was issued, those of distinguished ecclesiastics. John's decree, then, was neither intended to hamper the development of chemistry, nor did it accidentally prevent those who were most closely in touch with the ecclesiastical authorities from pursuing their studies. Those, of course, who knew anything of the character of the author, would not expect it to interfere with the true progress of science. As we shall see in the next chapter, Pope John XXII. was really one of the most liberal patrons of education and of science in history.