shape, and position of the teeth of many more monkeys than I know the names of to-day. Before and from the time of " The Natural History of the Teeth," by John Hunter (2d ed., 1778), or Nasmyth's "Researches on the Teeth " (London, 1839), to the present day, the teeth have shared the care and study of the anatomists of all countries. If, beside those I have enumerated, I were to pick out the names of such men as have done most for the anatomical knowledge of the teeth, I should mention Leuwenhoeck (1678), who discovered the spiral dental canaliculi; Purkinje, Arnold, Goodsir, Mareusen, Kolliker, Waldeyer, and Charles S. Tomes. By them the accurate histology of the teeth has been studied in addition to their coarse anatomy.

Chemistry has also come in for its share of work and result. The teeth of man and animals,—old and young animals,—diseased and healthy teeth, became the subjects of exact analysis, with which the names of Berzelius and Lehmann are intimately connected. But comprehensive knowledge of the living organism or any of its parts is not possible without acquaintance with its development. Modern medicine is built up, to a great part, on embryology. Many of the diseases of the young and old, and anomalies of structure and function, are best explained by the history of the embryo and fetus. Now, in dental science the study of embryology has been as fertile as in any other branch of medical knowledge. Since Goodsir and Arnold first explained the dental follicles by cutaneous vesicles, connected with the oral mucous membrane (or rather its epithelium) of the embryo from which they are duplicatures, immerging into the developing jaws, in which thus grooves are formed, many of the arrests of development and diseases of the teeth have found their explanation in the numerous results of the patient researches of embryologists. Among the more prominent facts known to all is, for instance, the absence of teeth and the consequent smallness of the bone. The existence of maxillary cysts and the presence of bones and teeth in them finds its ready explanation in embryological data. Amongst the tumors it is principally odontoma which owes its origin to an embryonal maldevelopment of the dental pulp. Nor is it at all improbable that Cohnheim is correct in many instances with his theory that all the malignant tumors of later life are due originally to improper retention and defective evolution of embryonal cells. In that case the embryology of the teeth and jaws would have to account for sarcoma, fibroma, myxoma, carcinoma, and osteoma, in connection with those organs.

Besides these growths, the embryo and fetus are responsible for a great many changes in the appearance and condition of the teeth of the infant and adult. Fetal diseases, such as syphilis, affect the teeth forever. Now, it is true that Hutchinson's doctrine in regard to the peculiar shape of the permanent teeth of children bom with hereditary syphilis is greatly exaggerated; but early decay, friability, diminutive size, ragged appearance, and speedy decay of the temporary teeth of syphilitic infants are positive facts. Premature ossification of the cranial sutures and fontanels, whether completed or not before birth, exerts a lasting influence on the protrusion and development of the teeth. Not only will they appear long before their normal time, but the order in which they appear is changed. In nine out of ten such cases, before and since I first wrote on the subject of premature ossification, in 1858,1 found the upper incisors to come first, and the number of teeth before the first year of life is completed to be in excess of the usual figure.

The diseases developed after birth have a great influence on the teeth. The transparent teeth of the consumptive; the friability of the teeth after serious illness, such as typhoid fever, which reminds one of the rapid shedding of their kin, the hair; the horizontal marks on the teeth, either temporary or permanent, which are due to diseases undergone at the time when that particular tooth or set of teeth was in process of rapid formation and protrusion, so that a serious illness can be known to have existed at a certain period of life,—all these circumstances point to the most intimate connection of the dental organs with the human organism. Let me add only one instance, viz., the influence that rachitis has on both teeth and bones The cranial sutures and fontanels will close late; the protrusion of the temporary incisors is greatly retarded, or interrupted; the teeth are small, soft, and friable, and easily decayed. It is only the permanent teeth which, in the process of eburnification of the whole osseous tissue during the protracted recovery, are large, hard, solid, and yellowish. Both jaws (but particularly the lower) are of small or diminutive size compared with the large skull; the lower jaw does not reach the normal line, and is rotated so that the teeth are turned inwards. All these changes form an important part of pathological anatomy, one of the best studies of which that I am acquainted with is the "Atlas of the Pathology of the Teeth," by Heider and Wedl. Perhaps, however, for the practice of your special profession the direct lesions of the tooth are of the greatest importance. Both caries and necrosis require the special study spent on the same processes when occurring in other living tissues. In this respect, as in many others, the dental specialist shares the interests and requires the study of the general physician and surgeon.

In regard to many other questions, it is the same. Is there a dentist who would be satisfied with the fact that teeth will fall out in advanced age? There is none who can do without understanding the process of the ossification of the pulp, the nature of the atheromatous obliteration of the small arteries, and the occlusion of the canaliculi of the dentine. Nor is there any one who could do without the exact knowledge of the histology of the gums, if he means to have an explanation of the fact that follicular stomatitis will not affect the gums, but that they will easily be destroyed by the ulcerative process first described by Tonnelet.

If I have spoken of normal and pathological anatomy, of embryology and surgery, I ought not to forget the direct connection dental art and science have with so-called internal medicine. It implies a great deal of general study, both anatomical and pathogical, on the part of a medico-dental man to give an account of those cases in which dental diseases were resulting in amaurosis or suppurative meningitis, or where the simple extraction of a tooth wras followed by dangerous or fatal hemorrhage. What is its diagnosis in an individual case? Is there an aneurism of the infra-maxillary artery or a branch? Is it a case of hemophilia? Grandidier has collected twelve cases in which this peculiar disposition to bleeding was the cause of death after extraction. Let me allude, finally, with a few words only, to a subject of vast interest to everybody, male and female, old and young,—particularly the young; the old, too, it is true, for the question of the so-called third dentition of the old and superannuated is perhaps not yet settled to everybody's complete satisfaction. The young, however, are mainly interested in the question of the first (also the second) dentition. Is there any disease or ailment which has not been connected with the poor little teeth both inside and outside the jaw? Everything in the mouth, from the erosion and ulceration of the frasnum of the tongue, resulting from friction over the sharp, isolated two central lower incisora during whooping-cough, to follicular stomatitis, pharyngeal abscess, and enlarged tonsils; everything from coated tongue to cholera infantum, epidemic dysentery or intussusception of the bowels; from colic to convulsions; from sore ears to curved limbs,—everything has been attributed to dentition. If it were true, it would be the most pardonable of all pious wishes that nature might not supply us with that dangerous gift at all, but trust us to the gentle care of the modern dentists, who will supply teeth without diarrhea, pneumonia, and convulsions. The question of dentition is really a very serious one, and deserves the closest attention of every one of us. Superstitions in medicine will not die out, or will die hard. One of the worst is the readiness with which both ignorance on the part of the public and incomplete diagnoses on the part of the practitioner contribute to the permanency of the error which explains every disease of infancy and childhood by the influence of teething. You, Mr. President and gentlemen, who are correctly supposed by the public to know all about teeth and teething, will have it in your power to gradually eradicate that prejudice, which is as dangerous as it is ludicrous. To our successors many of the present beliefs will appear as preposterous as we deem some of those of past centuries on this subject. Of these let me give a single example before I close. In 1595 Dr. Jacobus Horstius wrote a book, « Be Aureo Dente Maxillari Pueri Silesii." This golden tooth in the maxilla of the Silesian boy was accepted as sacred truth. It was unheard of before, but it was considered a fact. « The innate heat of the body and the earth had produced that tooth. The gold is deposited by the veins supply, ing the cavity. The golden tooth grows out of the bony root. The gold in the tooth is nourished, lives, and feels. The golden tooth is held tight by the soft gums;" and so on through a long string of sentences. What I here report is not a joke, but an extract from a serious book, written in a time when no gold was dug into teeth as nowadays, and no gold was dug out of practicing on teeth. Like that instance of three hundred years ago, much of the present orthodoxy in regard to teeth and teething which is still preached and believed will be stowed away in future with the golden tooth of the Silesian boy of Jacob Horst, M. D.

Mr. President, in this little sketch, which was indeed meant for the purpose not of teaching but of proving to you that I am aware myself of the importance of your studies-, and the close connection of medicine and dentistry, I have alluded to a few points only. Indeed, to-day there is hardly a subject of great pathological, histological, or biological import which does not belong to the domain and form part of the necessary education of a cultured gentleman who studies and practices dental medicine and surgery. As a last word, I may be permitted to mention only bacteriology. Leptothrix, oidium, the fungus of that most destructive disease, actinomycosis, —they claim your attention and fears as much as ours, even from an immediate practical point of view. Thus, if I understood the tendency of the time at all, and the scientific needs and tendencies of all cultured men in general medicine and its branches, I should say that dental science is one of the roots of a stem, one of the branches of a tree,—general medicine. And as the old philosopher said of himself, that nothing human was foreign to him, I should say that to the scientific and practical odontologist nothing medical is foreign.

Dr. J. Smith Dodge, Jr., in reply, said: Mr. President and gentlemen, when one has to speak as the mouth-piece of others, he will naturally feel a little embarrassed by the duty, and while I have something of that feeling with regard to a part of what falls to me this evening, I am happy to begin with words in which I have no doubt all who are here will heartily join,—that is, in expressing the gratification which we feel at the courteous welcome extended to the Odontological Society by the president of that larger society in whose rooms we meet to-night for the first time. There are dentists who have no care to hold any wider connections than that which binds them to the mouths of their individual patients; but as death swings his scythe and gathers in the harvest I am happy to say that the number of these grows smaller and smaller, and I think that very much the largest part of us really feel ourselves to be, and are glad to be recognized as being, cognate members of the great medical profession. Dr. Jacobi has stated how it is that in the course of things art necessarily precedes science. It has been eminently so with dentistry. So much of that which falls to us to do in relieving and preventing the suffering of mankind through defects of the teeth is of a mechanical nature, that it is not strange this has seemed for long years to constitute dentistry. It must have been so by the nature of the case. One cannot leave a suffering fellow being to writhe in anguish while one sits down to look through his microscope, or consult his books, or make some chemical test. The first thing to be done is to relieve this human need that comes to us, and after that we may sit down and study out the case and see what, in the largest light of science we can throw upon it, it means, and how in other cases the like may be prevented. So art with us has come first.

Then there is another point, which it did not occur to the doctor to bring in. I remember that Mr. Huxley has somewhere defined the process of scientific investigation to consist of three steps: first, the observation of facts; second, the mental arrangement of those facts, with conclusions as to their relations to each other and their meaning; and, third, the testing of all these conclusions by going back again to the facts. Similarly, the dentist finds not only that the first demand is for the exercise of his art in the way of immediate relief or prevention, but that when, having done this, he has proceeded to deduce his scientific conclusions and to make the deepest and widest investigations he can, it becomes necessary for him again to go back, if not to the exercise, yet to the objects of his art, to verify or to overthrow the scientific deductions which he had made. So we are to-day, and we always must be, more of mechanics, perhaps, than any others who have part in the great duty and blessing of relieving the ills and defects of the human body; we are and always must be tied to these material objects, limitod in number and circumscribed in the locality which they occupy; we are tied down to manipulation and to observation of the teeth in situ, and we