of clinical instruction, the services of Boerhaave to the progress of after complete theoretical systems. The influence of the | As the organizer, and almost the constructor, of the modern method iatro-physical school was by no means exhausted; and in England, especially through the indirect influence of Sir Isaac Newton's (1642-1727) great astronomical generalizations, it took on a mathematical aspect, and is sometimes known as iatro-mathematical. This phase is most clearly developed in Archibald Pitcairne (1652-1713), who, though a determined opponent of metaphysical explanations, and of the chemical doctrines, gave to his own rude mechanical explanations of life and disease almost the dogmatic completeness of a theological system. His countryman and pupil, George Cheyne (16711743), who lived some years at Bath, published a new theory of fevers on the mechanical system, which had a great reputation. Their English contemporaries and successors, John Freind, William Cole, and Richard Mead, leaned also to mechanical explanations, but with a distrust of systematic theoretical completeness, which was perhaps partly a national characteristic, partly the result of the teaching of Sydenham and Locke. Freind (1675-1728) in his Emmenologia gave a mechanical explanation of the phenomena of menstruation. He is also one of the most distinguished writers on the history of medicine. Cole (1635-1716) (see above) published mechanical hypotheses concerning the causation of fevers which closely agree with those of the Italian iatro-mechanical school. More distinguished in his own day than any of these was Mead (1673-1754), one of the most accomplished and socially successful physicians of modern times. Mead was the pupil of the equally popular and successful John Radcliffe (1650-1714), who had acquired from Sydenham a contempt for book-learning, and belonged to no school in medicine but the school of common sense. Radcliffe left, however, no work requiring mention in a history of medicine. Mead, a man of great learning and intellectual activity, was an ardent advocate of the mathematical doctrines. "It is very evident," he says, "that all other means of improving medicine have been found ineffectual, by the stand it was at for two thousand years, and that, since mathematicians have set themselves to the study of it, men already begin to talk so intelligibly and comprehensibly, even about abstruse matters, that it is to be hoped that mathematical learning will be the distinguishing mark of a physician and a quack." His Mechanical Account of Poisons, in the first edition (1702), gave an explanation of the effects of poisons, as acting only on the blood. Afterwards he modified his hypothesis, and referred the disturbances produced to the nervous liquor," which he supposed to be a quantity of the "universal elastic matter" diffused through the universe, by which Newton explained the phenomena of light-i.e. what was afterwards called the luminiferous ether. Mead's treatise on The Power of the Sun and Moon over Human Bodies (1704), equally inspired by Newton's discoveries, was a premature attempt to assign the influence of atmospheric pressure and other cosmical causes in producing disease. His works contain, however, many original experiments, and excellent practical observations. James Keill (1673-1719) applied Newtonian and mechanical principles to the explanation of bodily functions with still greater accuracy and completeness; but his researches have more importance for physiology than for practical medicine. " Boerhaave.-None of these men founded a school-a result due in part to their intellectual character, in part to the absence in England of medical schools equivalent in position and importance to the universities of the Continent. An important academical position was, on the other hand, one of the reasons why a physician not very different in his way of thinking from the English physicians of the age of Queen Anne was able to take a far more predominant position in the medical world. Hermann Boerhaave (1668-1738) was emphatically a great teacher. He was for many years professor of medicine at Leiden, where he lectured five hours a day, and excelled in influence and reputation not only his greatest forerunners, Montanus of Padua and Sylvius of Leiden, but probably every subsequent teacher. The hospital of Leiden, though with only twelve beds available for teaching, became the centre of medical influence in Europe. Many of the leading English physicians of the 18th century studied there; Gerard Van Swieten (17001772), a pupil of Boerhaave, transplanted the latter's method of teaching to Vienna, and founded the noted Vienna school of medicine. Friedrich Hoffmann (1660-1742), like Boerhaave, owed his influence, and perhaps partly his intellectual characteristics, to his academical position. He was in 1693 appointed the first prothe elector Frederick III. Here he became, as did his contemporary fessor of medicine in the university of Halle, then just founded by and rival Stahl, a popular and influential teacher, though their university had not the European importance of Leiden. Hoffmann's "system was apparently intended to reconcile the opposing to have been much influenced by the philosophy of Leibnitz. His spiritual" and materialistic views of nature, and is thought medical theories rest upon a complete theory of the universe. Life depended upon a universally diffused ether, which animals breathe in from the atmosphere, and which is contained in all parts of the body. It accumulates in the brain, and there generates the "nervous fluid or pneuma-a theory closely resembling that of Mead on the "nervous liquor," unless indeed Mead borrowed it from Hoffmann. On this system are explained all the phenomena of life and disease. Health depends on the maintenance of a proper tone in the others by "atony," or want of tone. But it is impossible here to body-some diseases being produced by excess of tone, or spasm "; follow its further developments. Independently of his system, which has long ceased to exert any influence, Hoffmann made some contributions to practical medicine; and his great knowledge of chemistry enabled him to investigate the subject of mineral waters. He was equally skilful in pharmacy, but lowered his position by the practice, which would be unpardonable in a modern physician, of trafficking in secret remedies. ་་ George Ernest Stahl (1660-1734) was for more than twenty years professor of medicine at Halle, and thus a colleague of Hoffmann, whom he resembled in constructing a complete theoretical system, though their systems had little or nothing in common. Stahl's chief aim was to oppose materialism. For mechanical conceptions he substituted the theory of "animism "-attributing to the soul the functions of ordinary animal life in man, while the life of other creatures was left to mechanical laws. The symptoms of disease were explained as efforts of the soul to rid itself from morbid influences, the soul acting reasonably with respect to the end of self-preservation. The anima thus corresponds partly to the "nature of Sydenham, while in other respects it resembles the archeus of Van Helmont. Animism in its completeness met with little acceptance during the lifetime of its author, but influ enced some of the iatro-physical school. Stahl was the author of the theory of " phlogiston in chemistry, which in its day had great importance. Haller and Morgagni.-From the subtleties of rival systems it is a satisfaction to turn to two movements in the medicine of the 18th century which, though they did not extinguish the spirit of system-making, opened up paths of investigation by which the systems were ultimately superseded. These are physiology in the modern sense, as dating from Haller, and pathological anatomy, as dating from Morgagni. Albrecht von Haller (1708-1777) was a man of even more encyclopaedic attainments than Boerhaave. He advanced chemistry, botany, anatomy, as well as physiology, and was incessantly occupied in endeavouring to apply his scientific studies to practical medicine, thus continuing the work of his great teacher Boerhaave. Besides all this he was probably more profoundly acquainted with the literature and bibliography of medicine than any one before or since. Haller occupied in the new university of Göttingen (founded 1737) a position corresponding to that of Boerhaave at Leiden, and in like manner influenced a very large circle of pupils The appreciation of his work in physiology belongs to the history of that science; we are only concerned here with its influence on medicine. Haller's definition of irritability as a property of muscular tissue, and its distinction from sensibility as a property of nerves, struck at the root of the prevailing hypothesis respecting animal activity. It was no longer necessary to suppose that a halfconscious "anima" was directing every movement. Moreover, Haller's views did not rest on a priori speculation, but on numerous experiments. He was among the first to investigate the action of medicines on healthy persons. Unfortunately the lesson which his contemporaries learnt was not the importance of experiment, but only the need of contriving cther "systems" less open to objection; and thus the influence of Haller led directly to the theoretical subtleties of William Cullen and John Brown, and only indirectly and later on to the general anatomy of M. F. X. Bichat. The great name of Haller does not therefore occupy a very prominent place in the history of practical medicine. The work of Giovanni Battista Morgagni (1682–1771) had and still preserves a permanent importance beyond that of all the contemporary theorists. In a series of letters, De sedibus et causis morborum per anatomen indagatis, published when he was in his eightieth year, he describes the appearances met with at the post mortem examination as well as the symptoms during life in a number of cases of various diseases. It was not the first work of the kind. The Swiss physician, Théophile Bonet (1620-1689) had published his. Sepulcretum in 1679; and observations of post mortem appearances had been made by Montanus, P. Tulp, Raymond Vieussens, A.M. Valsalva, G. M. Lancisi, Haller and others. But never before was so large a collection of cases brought together, described with such accuracy, or illustrated with equal anatomical and medical knowledge. Morgagni's work at once made an epoch in the science. Morbid anatomy now became a recognized branch of medical research, and the movement was started which has lasted till our own day. The contribution of Morgagni to medical science must be regarded as in some respects the counterpart of Sydenham's. The latter had, in neglecting anatomy, neglected the most solid basis for studying the natural history of disease; though perhaps it was less from choice than because his practice, as he was not attached to a hospital, gave him no opportunities. But it is on the combination of the two methods-that of Sydenham and of Morgagni-that modern medicine rests; and it is through these that it has been able to make steady progress in its own field, independently of the advance of physiology or other sciences. The method of Morgagni found many imitators, both in his own country and in others. In England the first important name in this field is at the same time that of the first writer of a systematic work in any language on morbid anatomy, Matthew Baillie (17611823), a nephew of John and William Hunter, who published his treatise in 1795. Cullen and Brown. It remains to speak of two systematic writers on medicine in the 18th century, whose great reputation prevents them from being passed over, though their real contribution to the progress of medicine was not great-Cullen and Brown. William Cullen (1710-1790) was a most eminent and popular professor of medicine at Edinburgh. The same academical influences as surrounded the Dutch and German founders of systems were doubtless partly concerned in leading him to form the plan of a comprehensive system of medicine. Cullen's system was largely based on the new physiological doctrine of irritability, but is especially noticeable for the importance attached to nervous action. Thus even gout was regarded as a "neurosis." These pathological principles of Cullen are contained in his First Lines of the Practice of Physic, an extremely popular book, often reprinted and translated. More importance is to be attached to his Nosology or Classification of Diseases. The attempt to classify diseases on a natural-history plan was not new, having been commenced by Sauvages and others, and is perhaps not a task of the highest importance. Cullen drew out a classification of great and needless complexity, the chief part of which is now forgotten, but several of his main divisions are still preserved. " It is difficult to form a clear estimate of the importance of the last systematizer of medicine-John Brown (1735-1788)-for, though in England he has been but little regarded, the wide though shortlived popularity of his system on the Continent shows that it must have contained some elements of brilliancy, if not originality. His theory of medicine professed to explain the processes of life and disease, and the methods of cure, upon one simple principlethat of the property of "excitability," in virtue of which the "exciting powers," defined as being (1) external forces and (2) the functions of the system itself, call forth the vital phenomena sense, motion, mental function and passion." All exciting powers are stimulant, the apparent debilitating or sedative effect of some being due to a deficiency in the degree of stimulus: so that the final conclusion is that "the whole phenomena of life, health as well as disease, consist in stimulus and nothing else." Brown recognized some discases as sthenic, others as asthenic, the latter requiring stimulating treatment, the former the reverse; but his practical conclusion was that 97% of all diseases required a stimulating treatment. In this he claimed to have made the most " salutary reform because all physicians from Hippocrates had treated diseases by depletion and debilitating measures with the object of curing by elimination. It would be unprofitable to attempt a complete analysis of the Brunonian system; and it is difficult now to understand why it attracted so much attention in its day. To us at the present time it seems merely a dialectical construction, having its beginning and end in definitions: the words power, stimulus, &c., being used in such a way as not to correspond to any precise physical conceptions, still less to definite material objects or forces. One recommendation of the system was that it favoured a milder system of treatment than was at that time in vogue; Brown may be said to have been the first advocate of the modern stimulant or feeding treatment of fevers. He advocated the use of "animal soups or beef-tea. Further, he had the discernment to see that certain symptoms-such as convulsions and delirium, which were then commonly held always to indicate inflammation-were often really signs of weakness. " The fortunes of Brown's system (called, from having been originally written in Latin, the Brunonian) form one of the strangest chapters in the history of medicine. In Scotland, Brown so far won the sympathy of the students that riotous conflicts took place between his partisans and opponents. In England his system took little root. In Italy, on the other hand, it received enthusiastic support, and, naturally, a corresponding degree of opposition. The most important adherent to Brown's system was J. Rasori (1763-1837), who taught it as professor at Pavia, but afterwards substituted his own system of contra-stimulus. The theoretical differences between this and the "stimulus" theory need not be expounded. The practical difference in the corresponding treatment was very great, as Rasori advocated a copious use of bleeding and of depressing remedies, such as antimony. Joseph Frank (1774-1841), a German professor at Pavia, afterwards of Vienna, the author of an encyclopaedic work on medicine now forgotten, embraced the Brunonian system, though he afterwards introduced some modifications, and transplanted it to Vienna. Many names are quoted as partisans or opponents of the Brunonian system in Italy, but scarcely one of them has any other claim to be remembered. In Germany the new system called forth, a little later, no less enthusiasm and controversial heat. C. Girtanner (17601800) first began to spread the new ideas (though giving them out as his own), but Weikard was the first avowed advocate of the system. Röschlaub (1768-1835) modified Brown's system into the theory of excitement (Erregungstheorie), which for a time was extremely popular in Germany. The enthusiasm of the younger Brunonians in Germany was as great as in Edinburgh or in Italy, and led to serious riots in the university of Göttingen. In America the system was enthusiastically adopted by a noted physician, Benjamin Rush (1745-1813), of Philadelphia, who was followed by a considerable school. France was not more influenced by the new school than England. In both countries the tendency towards positive science and progress by objective investigation was too marked for any theoretical system to have more than a passing influence. In France, however, the influence of Brown's theories is very clearly seen in the writings of François J. V. Broussais, who, though not rightly classed with the system-makers, since his conclusions were partly based upon anatomical investigation, resembled them in his attempt to unite theory and practice in one comprehensive synthesis. The explanation of the meteoric splendour of the Brunonian system in other countries seems to be as follows. In Italy the period of intellectual decadence had set in, and no serious scientific ardour remained to withstand the novelties of abstract theory. In Germany the case was somewhat different. Intellectual activity was not wanting, but the great achievements of the 18th century in philosophy and the moral sciences had fostered a love of abstract speculation; and some sort of cosmical or general system was thought indispensable in every department of special science. Hence another generation had to pass away before Germany found herself on the level, in scientific investigation, of France and England. Before the theoretic tendency of the 18th century was quite exhausted, it displayed itself in a system which, though in some respects isolated in the history of medicine, stands nearest to that of Brown-that, namely, of Hahnemann (see HOMOEOPATHY). S. C. F. Hahnemann (1753-1844) was in conception as revolutionary a reformer of medicine as Paracelsus. He professed to base medicine entirely on a knowledge of symptoms, regarding all investigation of the causes of symptoms as useless. While thus rejecting all the lessons of morbid anatomy and pathology, he put forward views respecting the causes of disease which hardly bear to be seriously stated. All chronic maladies result either from three diseasespsora (the itch), syphilis or sycosis (a skin disease), or else are maladies produced by medicines. Seven-eighths of all chronic diseases are produced by itch driven inwards. (It is fair to say that these views were published in one of his later works.) In treatment of disease Hahnemann rejected entirely the notion of a vis medicatrix naturae, and was guided by his well-known principle 1 The itch (scabies) is really an affection produced by the presence in the skin of a species of mite (Acarus scabiei), and when this is destroyed or removed the disease is at an end. "similia similibus curantur," which he explained as depending on the law that in order to get rid of a disease some remedy must be given which should substitute for the disease an action dynamically similar, but weaker. The original malady being thus got rid of, the vital force would easily be able to cope with and extinguish the slighter disturbance caused by the remedy. Something very similar was held by Brown, who taught that indirect debility was to be cured by a lesser degree of the same stimulus as had caused the original disturbance. Generally, however, Hahnemann's views contradict those of Brown, though moving somewhat in the same plane. In order to select remedies which should fulfil the indication of producing symptoms like those of the disease, Hahnemann made many observations of the action of drugs on healthy persons. He did not originate this line of research, for it had been pursued, if not originated, by Haller, and cultivated systematically by Tommasini, an Italian "contra-stimulist "; but he carried it out with much elaboration. His results, nevertheless, were vitiated by being obtained in the interest of a theory, and by singular want of discrimination. In his second period he developed the theory of potentiality" or dynamization-namely, that medicines gained in strength by being diluted, if the dilution was accompanied by shaking or pounding, which was supposed to " potentialize increase the potency of the medicine. On this principle Hahnemann ordered his original tinctures to be reduced in strength to onefiftieth; these first dilutions again to one-fiftieth; and so on, even till the thirtieth dilution, which he himself used by preference, and to which he ascribed the highest " potentiality." From a theoretical point of view Hahnemann's is one of the abstract systems, pretending to universality, which modern medicine neither accepts nor finds it worth while to controvert. In the treatment of disease his practical innovations came at a fortunate time, when the excesses of the depletory system had only partially been superseded by the equally injurious opposite extreme of Brown's stimulant treatment. Hahnemann's use of mild and often quite inert remedies contrasted favourably with both of these. Further, he did good by insisting upon simplicity in prescribing, when it was the custom to give a number of drugs, often heterogeneous and inconsistent, in the same prescription. But these indirect benefits were quite independent of the truth or falsity of his theoretical system. or highest importance. William Heberden (1710-1801), a London physician, called by Samuel Johnson ultimus Romanorum, "the last of our learned physicians," left a rich legacy of practical observations in the Commentaries published after his death. More important in their results than any of these works were the discoveries of EDWARD JENNER (q.v.), respecting the prevention of small-pox by vaccination, in which he superseded the partially useful but dangerous practice of inoculation, which had been introduced into England' in 1721. The history of this discovery need not be told here, but it may be pointed out that, apart from its practical importance, it has had great influence on the scientific study of infectious diseases. The name of John Pringle (1707-1782) should also be mentioned as one of the first to study epidemics of fevers occurring in prisons and camps. His work, entitled Observations on the Diseases of an Army, was translated into many European languages and became the standard authority on the subject. In Germany the orly important school of practical medicine was that of Vienna, as revived by Gerard van Swieten (1700-1772), a pupil of Boerhaave, under the patronage of Maria Theresa. Van Swieten's commentaries on the aphorisms of Boerhaave are thought more valuable than the original text. Other eminent names of the same school are Anton de Haën (1704-1776), Anton Störck (1731-1803), Maximilian Stoll (1742-1788), and John Peter Frank (1745-1821), father of Joseph Frank, before mentioned as an adherent of the Brownian system, and like his son carried away for a time by the new doctrines. This, the old "Vienna School," was not distinguished for any notable discoveries, but for success in clinical teaching, and for its sound method of studying the actual facts of disease during life and after death, which largely contributed to the establishment of the "positive medicine" of the 19th century. One novelty, however, of the first importance is due to a Vienna physician of the period, Leopold Auenbrugger (17221809), the inventor of the method of recognizing diseases of the chest by percussion. Auenbrugger's method was that of direct percussion with the tips of the fingers, not that which is now used, of mediate percussion with the intervention of a finger or plessimeter; but the results of his method were the same and its value nearly as great. Auenbrugger's great Positive Progress in the 18th Century.-In looking back on the repeated attempts in the 18th century to construct a universal system of medicine, it is impossible not to regret the waste of brilliant gifts and profound acquirements which they involved. It was fortunate, however, that the accumulation of positive knowledge in medicine did not cease. While Germany and Scotland, as the chief homes of abstract speculation, gave birth to most of the theories, progress in objective science was most marked in other countries-in Italy first, and after-work, the Inventum novum, was published in 1761. The new wards in England and France. We must retrace our steps a little to enumerate several distinguished names which, from the nature of the case, hardly admit of classification. In Italy the tradition of the great anatomists and physiologists of the 17th century produced a series of accurate observers and practitioners. Among the first of these were Antonio Maria Valsalva (1666–1723), still better known as an anatomist; Giovanni Maria Lancisi (1654-1720), also an anatomist, the author of a classical work on the diseases of the heart and aneurisms; and Ippolito Francisco Albertini (1662-1738), whose researches on the same class of diseases were no less important. In France, Jean Baptiste Sénac (1693-1770) wrote also an important work on the affections of the heart. Sauvages, otherwise F. B. de Lacroix (1706-1767), gave, under the title Nosologia methodica, a natural-history classification of diseases; Jean Astruc (1684-1766) contributed to the knowledge of general diseases. But the state of medicine in that country till the end of the 18th century was unsatisfactory as compared with some other parts of Europe. In England the brilliancy of the early part of the century in practical medicine was hardly maintained to the end, and presented, indeed, a certain contrast with the remarkable and unflagging progress of surgery in the same period. The roll of the College of Physicians does not furnish many distinguished names. Among these should be mentioned John Fothergill (1712-1780), who investigated the "putrid sore throat" Bow called diphtheria, and the form of neuralgia popularly known as tic douloureux. A physician of Plymouth, John Huxham (1694-1768), made researches on epidemic fevers, in the spirit of Sydenham and Hippocrates, which are of the practice was received at first with contempt and even ridicule, and afterwards by Stoll and Peter Frank with only grudging approval. It did not receive due recognition till 1808, when J. N. Corvisart translated the Inventum novum into French, and Auenbrugger's method rapidly attained a European reputation. Surpassed, but not eclipsed, by the still more important art of auscultation introduced by R. T. H. Laennec, it is hardly too much to say that this simple and purely mechanical invention has had more influence on the development of modern medicine than all the " systems" evolved by the most brilliant intellects of the 18th century. Rise of the Positive School in France.-The reform of medicine in France must be dated from the great intellectual awakening caused by the Revolution, but more definitely starts with the researches in anatomy and physiology of Marie François Xavier Bichat (1771-1802). The importance in science of Bichat's classical works, especially of the Anatomie générale, cannot be estimated here; we can only point out their value as supplying a new basis for pathology or the science of disease. Among the most ardent of his followers was François Joseph Victor Broussais (1772-1838), whose theoretical views, partly founded on those of Brown and partly on the so-called vitalist school of Théophile Bordeu (1722-1776) and Paul Joseph Barthez (1734-1806), differed from these essentially in being avowedly based on anatomical observations. Broussais's chief aim was to find an anatomical basis for all diseases, but he is especially known for his attempt to explain all fevers as a consequence of irritation or inflammation of the intestinal canal (gastroentérite). A number of other maladies, especially general diseases and those commonly regarded as nervous, were attributed to the same cause. It would be impossible now to trace the steps which led to this wild and long since exploded theory. I the same influence as Lavoisier in France. The English school It led, among other consequences, to an enormous misuse of of medicine was also profoundly stirred by the teachings of bleeding. Leeches were his favourite instruments, and so much the two brothers William and John Hunter, especially the so that he is said to have used 100,000 in his own hospital latter-who must therefore be briefly mentioned, though wards during one year. He was equalled if not surpassed their own researches were chiefly concerned with subjects in this excess by his follower Jean Bouillaud (1796-1881), known lying a little outside the limits of this sketch. William Hunter for his important work on heart diseases. Broussais's system, | (1718-1783) was known in London as a brilliant teacher of to which he gave the name of Médecine physiologique," anatomy and successful obstetric physician; his younger brother did much indirect good, in fixing attention upon morbid changes and pupil, John Hunter (1728-1793), was also a teacher of in the organs, and thus led to the rise of the strongly opposed anatomy, and practised as a surgeon. His immense contribuanatomical and pathological school of Corvisart, Laennections to anatomy and pathology cannot be estimated here, and Bayle. but his services in stimulating research and training investigators belong to the history of general medicine. They are sufficiently evidenced by the fact that Edward Jenner and Matthew Baillie were his pupils. post-mortem appearances Jean Nicolas Corvisart (1755-1821) has already been mentioned as the translator and introducer into France of Auenbrugger's work on percussion. He introduced some improvements in the method, but the only real advance was the introduction of mediate percussion by Pierre Adolphe Piorry (1794-1879) in 1828. The discovery had, however, yet to be completed by that of auscultation, or listening to sounds produced in the chest by breathing, the movements of the heart, &c. The combination of these methods constitutes what is now known as physical diagnosis. René Théophile Hyacinthe Laennec (1781-1826) was the inventor of this most important perhaps of all methods of medical research. Except for some trifling notices of sounds heard in certain diseases, this method was entirely new. It was definitely expounded in an almost complete form in his work De l'auscultation médiale, published in 1819. Laennec attached undue importance to the use of the stethoscope, and laid too much weight on specific signs of specific diseases; otherwise his method in its main features has remained unchanged. The result of his discovery was an entire revolution in the knowledge of diseases of the chest; but it would be a mistake to forget that an essential factor in this revolution was the simultaneous study of the condition of the diseased organs as seen after death. Without the latter, it is difficult to see how the information conveyed by sounds could ever have been verified. This increase of knowledge is therefore due, not to auscultation alone, but to auscultation combined with morbid anatomy, In the case of Laennec himself this qualification takes nothing from his fame, for he studied so minutely the relations of to symptoms during life that, had he not discovered auscultation, his researches in morbid anatomy would have made him famous. The pathologico-anatomical method was also followed with great zeal and success by Gaspard Laurent Bayle (1774-1816), whose researches on tubercle, and the changes of the lungs and other organs in consumption, are the foundation of most that has been done since his time. It was of course antecedent to the discovery of auscultation. Starting from these men arose a school of physicians who endeavoured to give to the study of symptoms the same precision as belonged to anatomical observations, and by the combination of both methods made a new era in clinical medicine. Among these were Auguste François Chomel (1788-1858), Pierre Charles Alexandre Louis (1787-1872), Jean Cruveilhier (1791-1874) and Gabriel Andral (1797-1876). Louis, by his researches on pulmonary consumption and typhoid fever, had the chief merit of refuting the doctrines of Broussais. In another respect also he aided in establishing an exact science of medicine by the introduction of the numerical or statistical method. By this method only can the fallacies which are attendant on drawing conclusions from isolated cases be avoided; and thus the chief objection which has been made to regarding medicine as an inductive science has been removed. Louis's method was improved and systematized by Louis Denis Jules Gavarret (1809-1890); and its utility is now universally recognized. During this brilliant period of French medicine the superiority of the school of Paris could hardly be contested. We can only mention the names of Pierre Bretonneau (1771-1862), Louis Léon Rostan (1790-1866), Jean Louis D'Alibert (1766-1837), Pierre François Olive Rayer (1793-1867) and Armand Trousseau (1801-1866), the eloquent and popular teacher. English Medicine from 1800 to 1840.-The progress of medicine in England during this period displays the same characteristics as at other times, viz. a gradual and uninterrupted development, without startling changes such as are caused by the sudden rise or fall of a new school. Hardly any theoretical system is of English birth; Erasmus Darwin (1731-1802), the grandfather of the great Charles Darwin, alone makes an exception. In his Zoonomia (1794) he expounded a theory of life and disease which had some resemblance to that of Brown, though arrived at (he says) by a different chain of reasoning. Darwin's work shows, however, the tendency to connect medicine with physical science, which was an immediate consequence of the scientific discoveries of the end of the 18th century, when Priestley and Cavendish in England exercised The same scientific bent is seen in the greater attention paid to morbid anatomy (which dates from Baillie) and the more scientific method of studying diseases. An instance of the latter is the work of Robert Willan (1757-1812) on diseases of the skin-a department of medicine in which abstract and hypothetical views had been especially injurious. Willan, by following the natural-history method of Sydenham, at once put the study on a sound basis; and his work has been the starting-point of the most important modern researches. About the same time William Charles Wells (1757-1817), a scientific investigator of remarkable power, and the author of a celebrated essay on dew, published observations on alterations in the urine, which, though little noticed at the time, were of great value as assisting in the important discovery made some years afterwards by Richard Bright. These observers, and others who cannot be mentioned here, belong to the period when English medicine was still little influenced by the French school. Shortly after 1815, however, when the continent of Europe was again open to English travellers, many English doctors studied in Paris, and the discoveries of their great French contemporaries began to be known. The method of auscultation was soon introduced into England by pupils of Laennec. John Forbes (1787-1861) in 1824, and William Stokes (1804-1878) of Dublin in 1825, published treatises on the use of the stethoscope. Forbes also translated the works of Laennec and Auenbrugger, and an entire revolution was soon effected in the knowledge of diseases of the chest. James Hope (1801-1841) and Peter Mere Latham (1789-1875) further developed this subject, and the former was also known for his researches in morbid anatomy. The combination of clinical and anatomical research led, as in the hands of the great French physicians, to important discoveries by English investigators. The discovery by Richard Bright (1789-1858) of the disease of the kidneys known by his name proved to be one of the most momentous of the century. It was published in Reports of Medical Cases 1827-1831. Thomas Addison (17931860) takes, somewhat later, a scarcely inferior place. The remarkable physiological discoveries of Sir Charles Bell (17741842) and Marshall Hall (1790-1857) for the first time rendered possible the discrimination of diseases of the spinal cord. Several of these physicians were also eminent for their clinical teaching-an art in which Englishmen had up till then been greatly deficient. Although many names of scarcely less note might be mentioned among the London physicians of the early part of the century, we must pass them over to consider the progress of medicine in Scotland and Ireland. In Edinburgh the admirable teaching of Cullen had raised the medical faculty to a height of prosperity of which his successor, James Gregory (1758-1821), was not unworthy. His nephew, William Pulteney Alison (1790-1859), was even more widely known. These great teachers maintained in the northern university a continuous tradition of successful teaching, which the possible in London. Nor was the northern school wanting in special difference in academical and other circumstances rendered hardly investigators, such as John Abercrombie (1780-1844), known for his work on diseases of the brain and spinal cord, published in 1828. and many others. Turning to Ireland, it should be said that the Dublin school in this period produced two physicians of the highest distinction. Robert James Graves (1796-1853) was a most eminent clinical teacher and observer, whose lectures are regarded as the model of clinical teaching, and indeed served as such to the most | Bell, Bright, Graves and others of the British school, quickly popular teacher of the Paris school in the middle of this century, made itself felt abroad. Trousseau. William Stokes (1804-1878) was especially known for his works on diseases of the chest and of the heart, and for his clinical teaching. German Medicine from 1800 to 1840.-Of the other countries of Europe, it is now only necessary to mention Germany. Here the chief home of positive medicine was still for a long time Vienna, where the "new Vienna school" continued and surpassed the glory of the old. Joseph Skoda (1805-1881) extended, and in some respects corrected, the art of auscultation as left by Laennec. Karl Rokitansky (1804-1878), by his colossal labours, placed the science of morbid anatomy on a permanent basis, and enriched it by numerous discoveries of detail. Most of the ardent cultivators of this science in Germany in the next generation were his pupils. In the other German schools, though some great names might be found, as Moritz Heinrich Romberg (1795-1873), the founder of the modern era in the study of nervous diseases, the general spirit was scholastic and the result barren till the teaching of one man, whom the modern German physicians generally regard as the regenerator of scientific medicine in their country, made itself felt. Johann Lucas Schönlein (1793-1864) was first professor at Würzburg, afterwards at Zürich, and for twenty years at Berlin (from 1839-1859). Schönlein's positive contributions to medical science were not large; but he made in 1839 one discovery, apparently small, but in reality most suggestive, namely, that the contagious disease of the head called favus is produced by the growth in the hair of a parasitic fungus. In this may be found the germ of the startling modern discoveries in parasitic diseases. His systematic doctrines founded the so-called "natural history school"; but his real merit was that of the founder or introducer of a method. In the words of H. Häser: Schönlein has the incontestable merit of having been the first to establish in Germany the exact method of the French and the English, and to impregnate this method with the vivifying spirit of German research." (J. F. P.) 64 Modern Progress.-In recent times the positive bent of modern knowledge and methods in other spheres of science and thought, and especially in biology, has influenced medicine profoundly. Minuter accuracy of observation was inculcated by the labours and teaching of the great anatomists of the 17th century; and, for modern times, experimental physiology was instituted by Harvey, anatomy having done little to interpret life in its dynamic aspects. For medicine in England Harvey did what William Gilbert did for physics and Robert Boyle for chemistry: he insisted upon direct interrogation of natural processes, and thereby annihilated the ascendancy of mere authority, which, while nations were in the making, was an essential principle in the welding together of heterogeneous and turbulent peoples. The degradation of medicine between Galen and Harvey, if in part it consisted in the blind following of the authority of the former physician, was primarily due to other causes; and its new development was not due to the discovery of the experimental method alone: social and political causes also are concerned in the advance even of the exact sciences. Among such contributory causes is the more familiar intercourse of settled nations which we enjoy in our own day; the ideas of one nation rapidly permeate neighbouring nations, and by the means of printed books penetrate into remoter provinces and into distant lands. Hence the description of the advance of medicine in western Europe and America may for the latest stage be taken as a whole, without that separate treatment, nation by nation, which in the history of earlier times was necessary. Italy lost the leading place she had taken in the new development of science. The several influences of modern Germany, France and America became of the first importance to English medicine; but these tides, instead of pursuing their courses as independent streams, have become confluent. The work of Theodor Schwann (1810-1882), Johannes Müller (18091875), Rudolph Virchow and Karl Ludwig (1816-1895) in Germany, of R. T. H. Laennec and Claude Bernard in France, was accepted in England, as that of Matthew Baillie, Charles The character of modern medicine cannot be summed in a word, as, with more or less aptness, that of some previous periods may be. Modern medicine, like modern Experiscience, is as boldly speculative as it has been in mental any age, and yet it is as observant as in any natural Method istic period; its success lies in the addition to these recognized. qualities of the method of verification; the fault of previous times being not the activity of the speculative faculty, without which no science can be fertile, but the lack of methodical reference of all and sundry propositions, and parts of propositions, to the test of experiment. In no department is the experimental method more continually justified than in that of the natural history of disease, which at first sight would seem to have a certain independence of it and a somewhat exclusive value of its own. Hippocrates had no opportunity of verification by necropsy, and Sydenham ignored pathology; yet the clinical features of many but recently described diseases, such, for example, as that named after Graves, and myxoedema, both associated with perversions of the thyroid gland, lay as open to the eye of physicians in the past as to our own. Again, to the naturalist the symptoms of tabès dorsalis were distinctive enough, had he noted them. No aid to the trained eye was necessary for such observations, and for many other such; yet, if we take Sir Thomas Watson (1792-1882) as a modern Sydenham, we may find in his lectures no suspicion that there may be a palsy of muscular co-ordination apart from deprivation of strength. Indeed, it does not seem to have occurred to any one to compare the muscular strength in the various kinds of paraplegia. Thus it was, partly because the habit of acceptance of authority, waning but far from extirpated, dictated to the clinical observer what he should see; partly because the eye of the clinical observer lacked that special training which the habit and influence of experimental verification alone can give, that physicians, even acute and practised physicians, failed to see many and many a symptomatic series which went through its evolutions conspicuously enough, and needed for its appreciation no unknown aids or methods of research, nor any further advances of pathology. We see now that the practice of the experimental method endows with a new vision both the experimenter himself and, through his influence, those who are associated with him in medical science, even if these be not themselves actually engaged in experiment; a new discipline is imposed upon old faculties, as is seen as well in other sciences as in those on which medicine more directly depends. And it is not only the perceptions of eye or ear which tell, but also the association of concepts behind these adits of the mind. It was the concepts derived from the experimental methods of Harvey, Lavoisier, Liebig, Claude Bernard, Helmholtz, Darwin, Pasteur, Lister and others which, directly or indirectly, trained the eyes of clinicians to observe more closely and accurately; and not of clinicians only, but also of pathologists, such as Matthew Baillie, Cruveilhier, Rokitansky, Bright, Virchowto name but a few of those who, with (as must be admitted) new facilities for necropsies, began to pile upon us discoveries in morbid anatomy and histology. If at first in the 18th century, and in the earlier 19th, the discoveries in this branch of medical knowledge had a certain isolation, due perhaps to the prepossessions of the school of Sydenham, they soon became the property of the physician, and were brought into co-ordination with the clinical phenomena of disease. The great Morgagni, the founder of morbid anatomy, himself set the example of carrying on this study parallel with clinical observation; and always insisted that the clinical story of the case should be brought side by side with the revelations of the necropsy. In pathology, indeed, Virchow's (1821-1902) influence in the transfiguration of this branch of science may almost be compared to that of Darwin and Pasteur in their respective domains. In the last quarter of the 19th century the conception grew clearer that morbid anatomy for the most part demonstrates |