Arculanus is particularly full in his directions for the preservation of the teeth. We are rather prone to think that prophylaxis is comparatively a modern idea, and that most of the principles of conservation of human tissues and the prevention of deterioration and disease are distinctly modern. It needs only a little consideration of Arculanus' instruction in the matter of the teeth, however, to undo any such false impression. For obvious reasons I prefer to quote Guerini's summation of this medieval student of dentistry's rules for dental hygiene:

"For the preservation of teeth—considered by him, quite rightly, a matter of great importance—Giovanni of Arcoli repeats the various counsels given on the subject by preceding writers, but he gives them as ten distinct canons or rules, creating in this way a kind of decalogue of dental hygiene. These rules are: (1) It is necessary to guard against the corruption of food and drink within the stomach; therefore, easily corruptible food—milk, salt fish, etc.—must not be partaken of, and after meals all excessive movement, running exercises, bathing, coitus, and other causes that impair the digestion, must also be avoided. (2) Everything must be avoided that may provoke vomiting. (3) Sweet and viscous food—such as dried figs, preserves made with honey, etc.—must not be partaken of. (4) Hard things must not be broken with the teeth. (5) All food, drink, and other substances that set the teeth on edge must be avoided. (6) Food that is too hot or too cold must be avoided, and especially the rapid succession of hot and cold, and vice versa. (7) Leeks must not be eaten, as such a food, by its own nature, is injurious to the teeth. (8) The teeth must be cleaned at once, after every meal, from the particles of food left in them; and for this purpose thin pieces of wood should be used, somewhat broad at the ends, but not sharp-pointed or edged; and preference should be given to small cypress twigs, to the wood of aloes, or pine, rosemary, or juniper and similar sorts of wood which are rather bitter and styptic; care must, however, be taken not to search too long in the dental interstices and not to injure the gums or shake the teeth. (9) After this it is necessary to rinse the mouth by using by preference a vinous decoction of sage, or one of cinnamon, mastich, gallia, moschata, cubeb, juniper seeds, root of cyperus, and rosemary leaves. (10) The teeth must be rubbed with suitable dentrifices before going to bed, or else in the morning before breakfast. Although Avicenna recommended various oils for this purpose, Giovanni of Arcoli appears very hostile to oleaginous frictions, because he considers them very injurious to the stomach. He observes, besides, that whilst moderate frictions of brief duration are helpful to the teeth, strengthen the gums, prevent the formation of tartar, and sweeten the breath, too rough or too prolonged rubbing is, on the contrary, harmful to the teeth, and makes them liable to many diseases."

All this is so modern in many ways that we might expect a detailed exact knowledge of the anatomy of the teeth and even something of their embryology from Arculanus. It must not be forgotten, however, that coming as he does before the Renaissance, the medical sciences in the true sense of the word are as yet unborn. Men are accumulating information for practical purposes but not for the classification and co-ordination that was to make possible the scientific development of their knowledge.

Giovanni of Arcoli's acquaintance with the anatomy of the teeth was rather sadly lacking. He does not know even with certainty the number of roots that the teeth have. This has been attributed to the fact that he obtained most of his information from books, and had not the time to verify descriptions that he had found. It has been argued from this that he was himself probably not a practical dentist, and turned to that specialty only as a portion of his work as a general surgeon, and that consequently he was not sufficiently interested to verify his statements. His chapters on dentistry would seem to bear out this conclusion to some extent, though the very fact that one who was himself not specially interested in dental surgery should have succeeded in gathering together so much that anticipates modern ideas in dentistry, is of itself a proof of how much knowledge of the subject there was available for a serious student of that time. The anatomy of the teeth continued to be rather vague until about the middle of the next century when Eustachius, whose investigations of the anatomy of the head have deservedly brought him fame and the attachment of his name to the Eustachian canal, wrote his "Libellus de Dentibus—Manual of the Teeth," which is quite full, accurate, and detailed. Very little has been added to the microscopic anatomy of the teeth since Eustachius' time. He had the advantage, of course, of being intimately in contact with the great group of Renaissance anatomists,—Vesalius, Columbus, Varolius, Fallopius, and the others, the great fathers of anatomy. Besides, his position as Papal Physician and Professor of Anatomy at the Papal Medical School at Rome gave him opportunities for original investigation, such as were not easily obtained elsewhere.

Arculanus can scarcely be blamed, therefore, for not having anticipated the Renaissance, and we must take him as merely the culmination of medieval knowledge with regard to anatomy and surgery. Medieval medical men did not have the time nor apparently the incentive to make formal medical science, though it must not be forgotten, as has been said, that they did use the knowledge they obtained by their own and others' observation to excellent advantage for the practical benefit of ailing humanity. The sciences related to medicine are conscious developments that follow the evolution of practical medicine, nor must it be forgotten that far from always serving as an auxiliary to applied medical science, often indeed in the history of medicine scientific pursuits have led men away into side issues from which they had to be brought back by some genius medical observer. As might be expected, then, it is with regard to the practical treatment and general consideration of ailments of the teeth that Giovanni of Arcoli is most interesting. In this some of his chapters contain a marvellous series of surprises.

Arculanus was probably born towards the end of the fourteenth century. The date of his death is variously placed as either 1460 or 1484, with the probability in favor of the former. From 1412 to 1427 he was professor at Bologna, where in accordance with the non-specializing tendencies of the time he did not occupy a single chair but several in succession. He seems first to have taught Logic, then Moral Philosophy, and finally Medicine. His reputation in medicine drew many students to the university, and his fame spread all over Italy. The rival University of Padua then secured him, and he seems to have been for some twenty years there. Later apparently he accepted a professor's chair at Ferrara, where the D'Estes were trying to bring their university into prominence. It was at Ferrara that he died. He was a man of wide reading, of extensive experience, both of men and medicine, and one of the scholars of his time. His works are, as we have said, mainly excerpts from earlier writers and particularly the Arabians, but they contain enough of hints drawn from his own observation and experience to make his work of great value.

While, as Gurlt remarks in his "History of Surgery," Arculanus' name is one of those scarcely known—he is usually considered just one of many obscure writers of the end of the Middle Ages—his writings deserve a better fate. They contain much that is interesting and a great deal that must have been of the highest practical value to his contemporaries. They attracted wide attention in his own and immediately succeeding generations. The proof of this is that they exist in a large number of manuscript copies. Just as soon as printing was introduced his books appeared in edition after edition. His "Practica" was printed in no less than seven editions in Venice. Three of them appeared before the end of the fifteenth century, which places them among the incunabula of printing.

Probably nothing in the history of human intellectual interest is more striking than the excellent judgment displayed by the editors who selected the works to be printed at this time. Very few of them were trivial or insignificant. Fewer still were idle speculations, and most of them were almost of classical import for literature and science. Four editions of this work were printed in Venice in the sixteenth century, one of them as late as 1560, when the work done by such men as Vesalius, Columbus, Eustachius, and Fallopius would seem to have made Arculanus out of date. The dates of the various editions are Venice, 1483, 1493, 1497, 1504, 1542, 1557, and 1560. Besides there was an edition printed at Basel in 1540.

Arculanus is said to have re-introduced the use of the seton, that is the method of producing intense counter-irritation by the introduction of some foreign body into an incision in the skin. We owe to him, too, according to Pagel in the chapters on medieval medicine in Puschmann's "Handbook of the History of Medicine," an excellent description of alcoholic insanity.