The splitting up of medicine into specialties, and the increase of its subordinate branches into schools.—so called,—resulted in great danger to the unity of medical science.
A return to the methods which combine science and practice—the so-called clinical-practical method—is again sought by men who have established the well-known Zeitschrift fur Klinische Medicin, under the management of Frerichs and Leyden,—a journal which has already done a great deal of good.
The versatile Bouchut, of Paris, has recently published a theory,—the so-called "Seminalism,"—for which the claim is made that he grants nothing to hypothesis, and everything to observation; its characteristic is that this new theory is also vitalistic,—in fact, the French have scarcely ever brought forth any other than vitalistic theories. Borden and Barthez, during the previous century, created the first French theory, which was followed out by Bichat, and later by Bouchut, who, as a matter of fact, owes much to Bichat. Bouchut teaches that beasts have an intelligence of instinct, and men one of abstraction; no beast oversteps the limits of animal thought, which is separated by an abyss from the productive thought of men; there is a proper kingdom of man, in accordance with his special nature; also, that the vital forces of men and of beasts are entirely different from each other, and that the principle of physical identity remains in the bodies of each, since the constantly renewed mass is formed in exact accordance with the original plans; in all the changes of his elements man is identical with man; all internal and external causes of disease modify, more or less, the vital force and its impressibility in the fluids or at some point in the economy, either increasing it or diminishing it. This theory, published in. 1873, claimed "in the abstraction of its promise and completeness of its conclusions to yield to none of its predecessors." Yet, even in France, the task of transforming medicine into a natural and exact science is far from being a fait accompli.
The most recent theories of disease are the result of microscopical study of germs,—the germ-theory, in fact,—and stand in the closest possible relation with the doctrine of spontaneous generation, fermentation, miasm, and contagion. In 1838 Ehrenberg regarded infusoria as animals, but Dujardin in 1841 expressed doubts, and Perty in 1852 affirmed that most forms classified as infusoria should be assigned to the vegetable kingdom, where, a little later, Naegeli relegated them. The correctness of this conclusion was proved by Cohn, who also perfected a classification. This particular form of investigation began in the twenties of the present century and assumed its present direction in the thirties and forties. Gaspard, in 1823, renewed the experiments of Haller, and injected into the veins of animals, not alone putrescent material, but the blood of other creatures suffering from the effect of such injections. Bassi, in 1835, discovered the cause of silk-worm disease, thereby giving special impulse to the theory of parasitism, and this was quickly followed by evidence of the existence of both vegetable and animal exciters of disease. Schoenlein, in 1839, demonstrated the fungus of favus; Vogel discovered the Oïdium albicans in 1840; Goodsir, the Sarcina ventriculi, in 1841; but the greatest influence upon the development of the parasitic, or germ-theory was the sequel to the discovery of the anthrax bacillus, by Davaine in 1850. In 1837 Latour and Schwann demonstrated that the cells, which were known even to Leeuwenhoeck, were actually vegetable forms, and Schulze had already pointed out that fermentation of fluids could only occur in the presence of extremely minute vegetable organisms; Chevreuil next showed that animal solids remained free from decomposition when protected from the access of germs; and in 1857 Pasteur demonstrated that fermentation and putrefaction were caused, not by chemical forms, as Liebig had taught, but simply by the agency of lower organisms, which he divided into aerobes and anaerobes; while in 1868 Chauveau queried as to whether morbific elements resided in the formed elements of germs or in their fluid constituents. Thus the theory of contagium vivum, for which Henle contended as early as 1821, was not forgotten. In Germany Klebs and Hueter became the prominent champions of this theory; Hallier had designated his so-called "Microsporon septicum," and introduced a method of fractional cultures. The views of Klebs were opposed by Billroth, who contended for his "phlogistic ferment" and "Coccobacteria septica," upon which he wrote an elaborate and extensively illustrated treatise; he also at that time opposed the specific character of the lower organisms as disease agents. Hallier's microsporon was refuted by Cohn, who studied and classified the various fungi, and distinguished between the pathogenic and the septicogenic,—that is, those which produced disease and those which produced ordinary putrefaction. Then came the experimental evidence of Davaine and Koch, who demonstrated the development of bacteria from spores. It is hardly necessary to discuss this theory further, but I may mention the labors of Panum and of Brieger, who deeply investigated the poisons produced by bacteria, to which are given the general titles of ptomaines and toxins.
It would be unjust, however, did I not mention the name of Lister in connection with the inestimable benefit that has accrued to surgery from the practical application of the theory of infection to wounds,—a measure that brought about an entire revolution in surgery and surgical technique, and an entire reversal of the statistics of operations; where thousands formerly died, thousands now live, their lives being indirectly due to the labors of this one man and his following.
I will add that it is necessary to realize the difference between life and death to appreciate the changes that have been brought about during the last score of years. Much that in former years was unjustifiable has become both justifiable and feasible; to-day patients, as a matter of course, live after operations which, so recently as when I was a student, were considered impossible, or if performed exposed the operator to the charge of manslaughter.
I have spoken of the impulse which came from Avenbrugger's invention of percussion, which was greatly extended through the translation of his work by Corvisart (1755-1821); the latter also excelled as a clinical teacher and pathological anatomist, and had much to do with the education of others of his confrères whose names are lustrous in history. Among the most celebrated was Laënnec (1781-1826), who, though brought up among most trying surroundings, early manifested a zeal for medicine. He became a field-surgeon in the French army soon after the Reign of Terror, and pushed his classical and medical studies with restless zeal. In 1815 his first experiments were made with the stethoscope, the invention of which was due to accident: in order to hear the sounds of the heart more clearly, lie one day applied a cylindrical roll of paper, and then immediately constructed the whole form of the stethoscope upon the principle now everywhere resorted to. In 1819 he published his work on Mediate Auscultation,—a treatise on prognosis in disease of the lungs and heart, based principally upon this new aid to investigation. The treatise was speedily translated into all the languages of Europe. After enjoying a large practice Laënnec succumbed to ill health at the early age of forty-five. He seems to have had but slight appreciation of his own services to medicine, and to have prided himself rather on his skill in riding horseback. Honor and fame, however, followed closely upon the publication of his well-known work, and the manuals of physical diagnosis which now find frequent mention in book catalogues, and come from various and wide sources are the legitimate outcome of Avenbrugger's and of Laënncc's pioneer treatises.
A versatile French writer who devoted especial attention to medical nomenclature was Piorry (1794-1879), to whom we are indebted for the pleximeter. The double stethoscope, a legitimate extension of Laënnec's simple instrument, was invented by Cammann, of New York, and can justly be claimed for American medicine. Other methods of physical examination—like spirometry, chest measurement, and study of expired air—have been introduced since 1846. The ophthalmoscope, which has been of such sterling service, and is based upon the simplest of principles, was the invention of the famous Helmholtz, but just deceased. The principle of endoscopy,—the illumination and visual examination of the various cavities of the human body,—the various specula, the spectroscope, the sphygmograph, the more accurate record of physical sounds, the application of electricity, and the employment of thermometry represent a few of the strides in the medical science of the present century, thereby aiding and perfecting the art of diagnosis, which, in turn, must ever necessarily form the basis for all rational treatment. Let no one complain that we are still so far from certainty in every case; the wonder is that so much has been discovered in so short a space of time.
Wonderful as have been these advances, the greatest achievements have accrued to the department of surgery, which Chamisso terms "the seeing portion of the healing art." The sixteenth century opened the way for checking of haemorrhages; the seventeenth accomplished great simplifications and improvement in the way of dressing wounds; the eighteenth gave a refining and elevating tendency to the study of applied practice, and raised surgery to a level with other branches of science; and now the nineteenth century has, toward its close, made surgery as nearly, perhaps, as it ever can be, an exact science, to which every other branch of science has been made contributory. The chain-saw, invented in 1806 by Jeffery, alone gave an impetus to resection, which was cultivated especially in Germany; to resection was added osteotomy by Heine and Maver; this, in turn, was succeeded by the so-called subcutaneous osteotomy of Langenbeck in 1854; Stromeyer introduced subcutaneous tenotomy in 1831, which was a very pronounced advance on all that had gone before; then came the introduction of anæsthesia, by which were made possible operations that had been beyond human endurance; by the introduction of the rubber bandage by Esmarch in 1873 bloodless methods were made possible. Pain and haemorrhage, the two greatest enemies of the conscientious surgeon, being thus almost annihilated, there was left but an apparently theoretical limit to what the surgeon might accomplish. Orthopaedic surgery, introduced by Delpech, was unknown prior to 1816; it was first practiced systematically by Stromeyer and popularized in France by Guerin. Operations on nerves were studied as special methods by Schuh, Wernher, and Nussbaum. Jobert and Simon abroad, and Sims and Emmet in the United States, by their studies of fistulæ peculiar to the genito-urinary tract in females, have conferred inestimable benefits upon suffering womanhood. So late as 1839 Vidal declared there did not exist in the history of surgery a single well-authenticated case of complete cure of vesicovaginal tear.
It is not my intention to more than barely refer to the living surgeons of to-day, or those who have but very recently passed away from us; but it would be an injustice to overlook Bernhard von Langenbeck and Theodor Billroth. The former, born in 1810 and deceased in 1887, was for a time a teacher of physiology, but subsequently became successor of Dieffenbach in the University of Berlin. The influence he exerted upon surgery in Germany and (since the decline of French precedence) upon surgery all over the world, has perhaps been greater than that of any one man since Dupuytren's time. He it was that introduced into surgical technique and surgical pathology the experimental method of which Johannes Müller was the great exponent; indeed, the relatively high importance which pathology is given to-day in every surgical curriculum is due more to his labors than to those of any other one man. Genial, learned, indefatigable, he was the ideal accomplished teacher. It would be impossible in any short résumé of his life and labors to do justice to so distinguished a man, to whom the profession owes so much. Perhaps the highest testimonial that could be given would be the enumeration of the men who were ever and always his enthusiastic admirers. Langenbeck was the founder of the German Congress of Surgeons, and for many years its president, and the permanent home this association has built for itself in Berlin bears his name; the surgical journal he founded has now passed its fiftieth volume, and is today the first periodical of its class in any country or language.