Class, l& Book. ! LIBRARY OF THE fi&Sfo Medical Society of the Co. of Kings. Given by.....: 'A'.:.}-.*,.....*.*..*.Z^~fe-^&^^*-- Besides the main topic this bonk also treats of Subject No. On page \ Subject No. On page huMsC*' 'MvM'.'Ms'y \f.''7- 7 INTRODUCTORY LECTURE. DELIVERED AT THE Commencement of tfje iFouttfj Sesoloa OF THE HHB2DIKBAIL (S(DIL2>UOT OF SOUTH CAROLINA » Notoemfcec 1827. BY SAMUEL HENRY DICKSON, M. D PROF. OF THE iNSTITUTES AND PRACTICE OF MEDICINE CHARLESTON, PRINTED BY W. RILEY, 125 CHURCH-^REEf 1820. "jfo r ita® ffTffaa* THE pleasure, gentlemen, with which I welcome you within our College, and resume the seat from which I am accustomed to address you, is of necessity tempered by se- rious reflection upon the nature and importance of the du- ties which are here incumbent on me. it is to be supposed that you have considered deeply and deliberately the sub- jects of our future discussions ;—that you are fully aware of the nature and variety of the objects comprised in the study of Medical Science. In proportion to the power which in- dividuals are called to exercise over their fellow men is their responsibility; and in no situation in life is such an extent of power given into the hands of human beings as belongs to the profession among whose members you have enlisted yourselves. To you are hereafter to be committed the avenues of life ; to you are to be entrusted the public and private safety. You are to direct the fostering attentions which must ripen the tender nursling into the hardy man.— You are to point out to anxious parents the mode in which their children are to be made to realize their hopes, and to enable them to shun the dangers which surround and me- nace them with destruction. You are to direct the physical, and in no little measure the moral and intellectual education of the youth of our country. To you she is to be thus in- debted for the robustness and hardihood of her soldiers and her labourers, the nerve and muscle of the body politic.— The more intellectual portions of society are to be especi- ally subjects of your future care—for literary and scientific 4 men are with rare exceptions invalids. You are to prolong the life of the statesman, to whom millions look up with awe and submission ; to heal the wounds of the leader, upon whom armies are dependant for guidance and victory.— The softer sex too, whose faces our customs of refined life " do not suffer the winds of heaven to visit too roughly," depend habitually upon professional prudence and judgment for the acquisition of that strength of constitution which will enable them to bear the harsh storms of fate, and fit them to be the mothers of a useful and healthy offspring.— To you are the rising and populous cities of our country to be indebted for a proper and successful system of medical police, by which they may avoid the evils almost essentially consequent upon the crowding within small spaces numerous human habitations, or by means of which they may counter- balance these evils by an equal amount of good. To you are to be entrusted at different times, and under infinitely various.circumstances, the lives and healths of individuals. You will be expected to unravel the most intricate compli- cation of symptoms ; to detect the lurking cause of evil, and to expel it from the house of life. It is to be your lotto alleviate suffering ; to avert impending danger, and to rescue for a time the trembling mortal from the grave—that gulf which sooner or later must swallow up all the joys and sor- rows, all the hopes and fears, and anxieties which agitate and annoy the race of man. I cannot for a moment imagine you, on your parts, insen- sible to the force of such reflections. The profession upon which you are entering is deservedly of high character and standing ; and a moderate degree of success in its pursuits will ensure you, thanks to the republican nature of our instir tutions and habits, the respectful consideration and regard of the community of which you may form a part. Yet you must not expect to partake of this standing, and to support this character, without assiduous and persevering exertion. The acquisition of medical knowledge can only be made to the extent that is proper, and indeed necessary tor your future -* - o usefulness and respectability, by the most intense industry and indefatigable application. Your attention in collecting facts and observations ; your memory in storing them up and preserving them ; and your judgment in selecting, ana- lysing and arranging them, and deducing from them, by cor- rect and logical processes of reasoning, the principles which they have developed,—will be exercised to the utmost from the very first stage of your progress. As you advance new and increasing demands will be made for the incessant em- ployment of every improving faculty. If such are the duties which are hereafter to demand your minds—if such the high destinies that await you—what words can properly express the responsibility of those who are to instruct you; to furnish you with the means of answer- ing the expectations formed by your parents, your friends, and the community. Among no class of men is error more dangerous, or truth more important to be clearly known and understood. You will be every day called upon for the practical application of such principles as you may have formed or adopted. If, therefore, we teach you any erro- neous doctrines, or in any manner or degree conceal from you the truth, we justly incur a censure severe in proportion to the extent of evil, and it may be unlimited, which is likely to follow from such neglect or misrepresentation. Of the accomplishment of a task so arduous as the prepa- ration for the duties of a teacher of medicine, we may ac- knowledge, applying the fervid, rational and pious language used by Milton, speaking, however, of a different subject— " This is not to be obtained but by devout prayer to the eternal Spirit, that can enrich with all utterance and know- ledge, and sends out his seraphim with the hallowed fire of his altar to touch and purify the lips of whom he pleases.— To this must be added industrious and select reading, steady observation, and insight into all seemly and generous arts and affairs." * Who does not shrink at the thought of being measured by so lofty a standard as this ? Yet such and so fitted have 6 been not a few of the professors of our divine science. Suok were Boerhaave, and Cullen, and Gregory, and Rush ; and to this honorable list we might add some living names too, if a selection of this sort were not invidious. And the num- ber of such men is every day encreasing ; and an enthusiastic spirit of improvement is diffusing itself throughout the schools of Europe and America, whieh must ultimately, and at no distant day, be productive of the most important influence throughout society. Earth, sea and air are eagerly ransack- ed for remedies with which we may repel the invasions and repair the ravages of disease, that enemy whose name is Le- gion. The Chemist, shut up in his sequestered laboratory, no longer deluded by empty dreams and golden visions, plies fur- nace, crucible and alembic, not to discover the philosopher's stone or the universal solvent, but to lay open the hidden treasures of nature ; to separate the closest and most tena- cious compounds ; to draw out her active and energetic principles from the combinations which have rendered them inert, or fitted them merely for the ordinary purposes of utility ; and present them in this concentrated form as a tri- bute to the healing art. The Botanist, through his know- ledge of the natural arrangement and family connexion by which the interesting tribes of vegetables are united toge- ther, can offer us a rational and plausible conjecture concern- ing each new discovered species, before subjecting us to the risk of experiment, what properties it may possess, and in what way it bids fair to be useful 'to us. The Anatomist has exhausted the wonders of our conformation in his anxious and unwearied investigations into the position, relative connexion and uses of parts. Physiology still opens an unlimited field of enquiry, and her fascinating discussions are engaging the attention of all classes of literary men. The principle by which we live, and move, and have -our being ; the ordinary phenomena of life, the actions in which these consist, the modes in which these actions are performed, the results of these several actions, the powers of the body, the various 7 faculties of the mind, the reciprocal and close connexion of our external and internal selves—all these are objects of in- tense interest. Discoveries in relation to these points are daily making ; and we are entitled to the confident hope that much of the obscurity which has hitherto hung over these subjects is about to be finally and forever dispelled. In our investigations concerning the nature of mind, the think- ing portion of our frames, Anatomy and Physiology have been lately brought strongly to the aid of Metapl>ysics; which in turn receives and gives light to those who are engaged in these researches. The study of Phrenology, although it has created much error, has assisted to develope much val- uable truth, and has-directed us indeed to the very best, or rather the only proper method of regarding the connexion of the mind with the body. Until of 4ate, ispeaking comparatively, Pathology has been little understood; but it has now assumed a regular form, and its principles are deduced so clearly from a long train of observations, as not to be easily shaken or overturned. Philosophers, applying the title in its widest extent, are eagerly'inquiring into the causes and sources of disease. With this viewthe face of the country is examined carefully in each region ; ^he nature of the soil—the conditions of atmos- phere, locally and generally, as in the influences of position and climate, are considered; the appearance of various forms of disease noted in connexion with the state of society, and habits ©f life; and peculiarities of external conformation carefcriiy iriarlied^whh the liabilities to suffering which they imply. The Practtkioner goes into the details of each indi- vidual case*with similar views ; to discover what cause has affected the Patient with deleterious force ; whence it de- rtoekl'it£power1 of doing injury, whether from without or from peculiarity ofC benhcent purposes ultimately, than a rational scep- ticism, which pauses, ponders, and examines before coming to a decision. Having thus become convinced of the power of medicines, we might safely look upon the value of the healing art as established, for it consists in the therapeutical association of these medicines ; but no ! our second class of doubters urge their objection to the safety and of consequence to the utility of such applications, on account of the assumed irregularity of the influences which they exert upon the bo- dy, and of our supposed want of power to control or direct these influences, to increase, or to check, or to counteract them when disproportioned in force to the stability of the pa- tient's constitution. The mixture of truth with error in this statement, entitles it to a deliberate answer, and this is best given by a reference to the history and progress of the art or science of medicine. In its earliest infancy, the aged were the natural physicians of each other, and of the young, for they had exclusively enjoyed the opportunity for the obser- vation of facts of the kind alluded to as forming the founda- tion of the popular confidence in medicines. After the tem- ples of Esculapius and other deities of the heathen mythology became receptacles of certain emblems intended as memori- als of cures performed and relief afforded, travellers who had visited these temples, and collected the histories of these memorials, were of course looked to for information and usefulness, and were esteemed in proportion to the attention they had paid to the subject, and their capacity for making use of these means of instruction. It was thus indeed that the first physicians were formed ; to the perfection of whose character it was necessary that they had visited many of these temples, the only Medical Schools, so to speak, of the time, and had become aged in the acquisition of these scat- tered minutiae of universal experience. Experience then was the true basis of the art of medicine ; but it evidently 14 could not remain long stationary, requiring to be placed on a broader and more extended basis. As new cases occurred, difficulties presented themselves, which at first it was only endeavoured to evade by looking for aprescriber of more en- larged observation or better memory, who might be provi- ded with the details of some attack of the same nature. When this resource failed, as it must often and indeed most frequently fail, nothing was left for the rude though perhaps sagacious practitioner but theory—the process of reasoning from things known to things unknown ; some remembered case was selected by him as being most similar to or least unlike the one under management, and the previous treat- ment of this served as a rule to guide him in his task of bold but cautious experiment. His failure or success gave a valuable lesson, and such experiments going on to be more and more frequently repeated, and the knowledge thus de- rived being communicated by tradition, in poetry as well as= prose, professional ambition was stimulated with the hope of discovery, and thus the courage and sagacity of a physician became passports to reputation in lieu of mere experience ; the combination of these endowments, natural and acquired, soon becoming as it is now the true means of attaining emi- nence and wealth. Men of even ordinary talent could not proceed in the course just pointed out, without clearly per- ceiving that certain general principles were developed by and deducible from the particular facts with which they be- came every day more and more familiar, and that these gen- eral principles were calculated in a most beneficial way to guide their future practice. The very existence, however, of settled or established general principles in medicine has been loudly and confident- ly denied by many ignorant and prejudiced pretenders to knowledge and philosophy, who love to refer for the support or illustration of their position to the difficulty or impossibil- ity of explaining, accounting for, or even clearly describing ultimate and minute phenomena and the agencies which pro- duce them, and to our incapacity and uncertainty in making 15 application of the general principles which we affirm our- selves to comprehend and confide in. But these objections lie as fairly against all other arts and sciences as against ours, with the exception, perhaps, of those which refer to the powers of numbers simply. A mathematical line is a crea- ture of the imagination—a mere idea ; it is not to occupy space, yet it is to be divisible into an infinite number of parts. The Natural Philosopher cannot even satisfactorily define matter, as it seems from the undecided debates whether we are to comprise under this title, or regard as mere qua- lities of substance, light, heat, electricity and magnetism ; and he talks as boldly and vaguely of his attractions, and re- pulsions, as we do of excitablity, and mobility. What claim has Legal science to be so considered if this objection be judged valid ? Professing to be fixed upon the eternal and immutable principles of justice and equity, and assuming that all its regulations are drawn directly from these first and pure sources, why has the "glorious uncertainty of the law" passed into a general proverb ? Nay, we will take a proud satisfaction in the comparison with a science, if it be one, whose professors confine themselves to rules of decision set up by judges fallible, prejudiced, and liable to be corrupted, and thus depart wilfully and openly from the original and avowed spirit of their massive and complicated, entangled and embarrassed system. We, on the other hand, incessant- ly advocate and pursue the practice of Codification, referr- ing to old and confirmed doctrines and principles, and admit- ting new and consistent ones, as often and as soon as observa- tion shall have noted them, reasoning deduced them from facts, and time and experience successively established them. We should laugh at him who pretended to guide himself by a mere reference to books of cases, which, though piled up higher than Pelion upon Ossa, can ne- ver reach the diversified disturbances to which man is not more liable in his external relations with others, than in the internal relations of the several parts of his frame. How infinitely preferable to this, the formation of successive 16 systems, even although these should be overthrown and des- troyed by the addition of a greater mass of facts to our stoek, and the acquisition of better defined and clearer in- formation. For my own part I confess that I am pleased to think and to speak of these changes and reverses in the doctrinal part of our science. I regard them as proofs of the boldness, and freedom, and intelligence of its votaries. We are not content with our present attainments, but press onward with higher views. Is this exultingly alleged as proof that its ac- tual state is imperfect ? This has been without hesitation though with regret acknowledged. And is the science of Chemistry—of Law—of Theology—is either of these so com- plete as to require or admit of no change ? I prefer the evils, if they must exist, of revolution to those of torpid in- difference; the convulsion of inordinate excitement to the quiet stillness of lethargy, or the tranquil repose of death. Let us appeal to history for the beneficial tendency of such continual agitation and discussion, such violent dispute con- cerning the various doctrinal and practical themes embraced within the scope of our profession. I will begin with the advances of modern Surgery, and although it is not my pro- vince to speak of the numerous operations, which, permit- ed by the minute anatomical knowledge of the parts to be removed or acted on, and invented by courage and ingenuity, have subtracted so much from the immense sum of human misery, and added so much innumerous instances to the dura- tion of human life, yet I must be allowed to exult in the application of medicine to the management of such cases, by the judicious employment of which organs are restored to health and usefulness which would formerly have been left a burden or condemned to extirpation ; deformities pre- vented which having once been allowed to occur are forever irremediable ; and important parts protected from the inroad of diseases that once knew no check, or none less severe than the knife, the caustic, or the hot iron. Of such value have these internal agents been found in the treat- 17 ment of external disease, that they now form an essential part of the implements ofChirurgery, and a pure Surgeon—a mere Operator,—is a character no longer to be heard of—no longer known to exist as I believe in the civilized world. Yet the time is but shortly past when this character belonged to a great body of the most esteemed surgeons. If we turn to the condition of ordinary Therapeutics, our retrospect is no less gratifying. If we should lay claim to nothing more than the mere admission, that the proportion of deaths in certain specified masses of population is no greater than it former- ly was, (and this will scarcely be denied us,) we say much in favour of our profession^-for the causes of death and dis- ease have been multiplying in modern times with a fright- ful and lamentable rapidity, and our art must be little less than divine, to have successfully resisted this headlong tor- rent of destruction. Excess of all kinds in the indulgence of passion and appetite has flowed upon us with the refine- ments of civilization, and men seem to have been maddened' Dy the restraints which they voluntarily imposed upon them- selves. The arts of cookery, and the chemical improve- ments in distillation and fermentation, have spurred on the dispositions to gluttony and intemperance. Thus some new forms of disease have been introduced; many ancient and well known maladies have been modified, and their malig- nant intensity increased ; and the constitutions of whole fa- milies, races and nations, have been so deteriorated as in a notable degree to be less fitted to resist the invasion, and repair the ravages of ordinary disease. Yet with the exi- gencies thus pointed out, have increased also the resources of our art. Fever, the principal ailment of Savage, as well as of Civilized men, has lost much of its terror, and much of its malignity. Who can doubt this if he reflects for a moment on the slender stock of rude remedies made use of by bar- barous tribes ; their sick, if not relieved at once by the harsh alternations of heat and cold, in the humid sometimes and sometimes in the dry form, were consigned to the conjuror with his spells, charms and incantations. Yet this was pro- bably a more successful series of applications to the sturdy frame and credulous spirits of savages, than the more modern 3 18 means of cure depended on so confidently, and with such ex- clusive reliance in the dark ages of medicine—namely, the internal administration of cordials and alexipharmics in all the various forms of stimulating dilution to the wretch, who shut up in a close room, heated by artificial fires, enclosed within impervious curtains, and covered with woollen cloths, was destined never more to breathe the fresh cool air. In alter- ing the mode of managing Small Pox alone to the present plan of moderate and cautious exposure, thousands of lives have been saved. And the mention of this most formidable pestilence reminds me, that it is not in its curative applica- tion alone, that our science has been heaping benefits upon man, it is no less entitled to admiration and gratitude for its preventive exertions. It can easily be proved, that taking into account the frequency of its appearance, the uni- versality of its extension, especially where population was crowded—the malignant tendencies it has display- ed, and the ill success with which its treatment was attemp- ted—this eruptive fever stands first on the dreadful list of human maladies. Taught by the Turks the practice of Inoculation, Europe gladly made use of this means of indi- vidual alleviation, though soon proved to be of doubtful ben- efit to communities, on account of its giving wings to the in- fection, by augmenting the number of subjects, and accumu- lating wide strewn masses of fomites. What gratitude then does she not owe to the discoverer and promulgator of the efficacy of Vaccine ? What remote region shall not ring with the name of Jenner—now in a double sense immor- tal ! who has been the most happy instrument of delivering our whole race from suffering, mutilation, deformity, and the most disgusting and miserable form of death. We speak of the inventor of gunpowder—the constructor of the steam engine—and of him who first applied it to navigation, as great men, as universal benefactors, and justly, for their la- bours have been productive of universally important results. What rank then shall we assign to this previously obscure Physician, who has conferred on mankind a benefit far great- er than either accident or ingenuity ever proffered to its acceptance. We, his brethren and successors, owe him a 19 double tribute, as having afforded us a glorious opportunity of exhibiting the disinterested benevolence which should be, and I conscientiously believe has ever been, peculiarly the characteristic of our divine science. Men cannot mistrust the motives of those who earnestly endeavour to spread the benefits of the Vaccine.* We are entitled to claim as further honors of our science, the general system of Prophylactic management, by which the encroachments of disease are so often resisted—its darts blunted—and its envenomed activity rendered inert. As the causes of disease become better known, this system will be extended so as ultimately to include every morbid affection, perhaps, to which the human constitution is liable. And this will be, if our efforts ever bring it to perfection, the most notable of all our triumphs; for as the best Surgeon is he who avoids most sedulously the necessity for operation, so the best Physician will be that one who can most regu- larly prevent attacks of illness. We have already done much in this way for the community ; by pointing out to our fellow citizens the sources of Endemics and local Epidemics, we have diminished both their violence and their frequency of occurrence. By investigating the nature of the several Contagions, we have endeavoured to distinguish them from non-contagious affections, and thus limit their spread, while we are to avoid all unnecessary restrictions upon commerce. I could stir your hearts as with the sound of a trumpet by the description of the devoted zeal with which these researches have been pressed by our profession. Some have inoculated themselves for the plague, and died martyrs in the cause of science. Others have passed nights and days with patients ill of yellow fever—have inhaled the exhalation from their foul and dying bodies, and have even introduced into the stomach, for experiment's sake, the most * Hahneraan, a celebrated German practitioner, boasts of having dis- covered in the influence of Belladonna, a preventive of Scarlatina, as certain as Vaccine is of small pox. We have as yet had no opportunity of testing the accuracy of his statements, but the periodicals of Ger- many have abounded with confirmatory accounts. If there is no error in this matter, the world will have gained much in an assured protec- tion against a formidable ailment in a second instance. 20 digusting of their secretions. Yet such men live in com- parative obscurity, and perish in oblivion, while the de- stroyers of the battle field are exalted and dignified, and loaded with wealth and honours ! In the department of Medical Jurisprudence, properly so styled, our labours have not been unblessed or unproductive. By an accurate investigation of the various states and condi- tions of the bodies of infants born living and dead, we have rescued many an unfortunate woman from the infamy and punishment of child murder ; while, on the other hand, we have occasionally "been able to make evident the guilt of the wretched mother, and thus aid in the suppression of a crime ,so heinous. It is often our happy office to interpose between the law and its destined victim the lunatic, whose halluci- nations render him morally incapable of wrong, and of con- sequence exculpate him from blame, and shield him from penalties denounced. Time would fail me if I were to go on to detail the numerous instances in which the discoveries and improvements of our science are turned to account in the administration of public justice. It is not however in this enlightened age, and in a community like our own, that Physicians are forced to defend the power of their remedies or the value of their art—and to but few objectors are we obliged to explain the well known and uni- versally understood grounds of our pretensions. Our pro- fession cannot here complain of coldness or neglect. " Ser. vants of servants" are we literally to our brethren, and our lives without the chance of acquiring high esteem and lofty .consideration, would be spent in a burdensome and unremit- ting drudgery, to which no man of talent or ambition would submit. We are abundantly repaid however for these our most toilsome and exhausting labours—not by pecuniary emolument, although independence and even wealth are by no means out of our reach ; we are fully repaid by the lux- urious gratification of doing good, and by the gratitude of those whom we have succoured ; by the prayers of the poor who are especially objects of our care and attention, and by the blessing of hundreds and thousands of those who but for our aid were ready to perish. 21 Can it be wondered at then that I should take a grave pleasure and delight in teaching a science whose objects are so lofty and noble ; whose aims so beneficent, and whose re- wards so glorious and satisfying. It should rather excite surprise if I could speak coldly on these themes, or if you could listen without excitement while I spoke. Would that I could chain your attention with the eloquence of a Rush or a Shippen ; or with the plain familiar language of a Wistar, convey the most important truths so gently and quietly into your minds that you might be even insensible to the effort of imbibing knowledge. But it is not every arm that can bend the bow of Ulysses, and in lieu of these high endowmeats all I have to offer is an enthusiastic confidence in our divine art; an ardent zeal in promoting its improvement, and an unsha- ken determination to devote my life to its cultivation. In the course of Lectures, which it is my province to de- liver in this place, we shall take a brief view of the most important facts, doctrines and principles of Physiology, Pa- thology and the Practice of Medicine in succession. Com- mencing with an examination of the structure and function of the perfect full grown and healthy man, we shall consider him first in his individual and insulated condition. His man- ner of taking and converting to aliment the materials of growth and supply, shall engage our attention—the agents by which these extraneous materials are introduced into the vessels destined to circulate and to bear them to each por- tion of the body as they are required for its uses; the organs and powers by which this circulation and distribution are ef- fected, the play of the infinitely diversified machinery whose actions are so incessant; the results of these several actions in the formation of new and important substances, and the se- veral modes in which the effete and useless portions of food and drink are got rid of, and removed as burdens from the bo- dy. We next proceed to contemplate him in his relations with the world around him. We examine the organs by which he sees and hears and smells ; we enquire into the phenome- na of taste and feeling. The complicated mechanism of the nervous system will afford us an inexhaustible object of admiration and study, that system through which all the 22 parts of our frames are vivified and excited and endowed with their peculiar powers, by which each separate organ or structure is intimately and indissolubly connected with every other, and above all, by which are shown forth the manifestations of mind, the evidences of intellectual as connected with physical qualities aud capacities. The pow- er of motion by which we act upon each other, and upon ourselves, by which we approach objects which attract, and recede from those which repel, disgust or annoy us; the voice by which we communicate most touchingly and effectually our hopes, our views and our desires,—these shall receive in turn due notice and discussion. Nor shall we omit to de- tail to you all that is known of the mysterious and interest- ing process of generation, by which though individuals perish the race is preserved, and successive centuries see new crea- tions born to inherit the thrill of pleasure and the ecstacies of joy; new victims doomed to suffer the anguish of despair and the agonies of dissolution. We shall trace for you the period of the initial deposit of the first atoms which go to constitute the human frame ; the gradual addition of parti- cles, a'-d the building up of its members in regular order un- til it arrives at the time of birth, is ushered into a new world and assumes a new mode of existence. We shall continue to point out the several changes which take place as the infant becomes the child, the youth, the adult, and fi- nally snail pace over with you in imagination the painful steps by which he declines into decrepitude and dotage, and describe to you the diminution of power and the decay of organization which gradually oppress the functions into lassitude, torpor and death. Nest we shall describe to you the same functions and organs in the state of disease and suffering. We shall in- vestigate carefully and in detail the various causes, exter- nal and internal, which have been supposed to exert upon the human body a morbid influence in the production of the various maladies which have so long and so sorrowfully vexed our race. We shall make you familiar with the history and phenomena of the most common and important of these, and shall attempt a rationale or explanatiou*of these 23 phenomena. We shall endeavour to ascertain the tendency of each disorder, and inform you of such lesions or injuries as it may in its progress have inflicted upon the organization which may have been its seat. Having thus endeavoured to procure for you an insight into the principles and doctrines of Pathology, we proceed to t|ie practical application of all that has been learned in the discussion of the Therapeutical branch of our science. And, on the threshhold of these essays, you will be remin- ded that the principal and most beneficent office of the Phy- sician is to prevent rather than to cure disease ; to effect if possible its absolute extinction ; to wage against it a war of extirmination. We must strike at, and if possible, ex- tirpate the causes which affect the health of individuals and communities. If we cannot succeed in this we must aim to obviate as far as we may their consequences and evade their force. Failing in this effort, we counteract by the power of remedies to a certain degree the intensity of the morbid influence, and by the same or similar means support the struggling and oppressed constitution. I will not, as some of my predecessors have done, exclaim against the in- troduction of Theory into the treatises on Practical Medicine. In subjects of this kind we cannot hope to obtain demonstra- tive certainty except with regard to a very few facts and doctrines ; we are obliged to reason onward from things known to things unknown, and make such additions and im- provements to the systems we have been engaged in building as time and opportunity may permit. If this is done cau- tiously and with requisite attention to the established rules of philosophising, it is an exercise well calculated to invigo- rate the mind and fit us for the better and more successful performance of our arduous duties. We shall endeavour to teach you the Diagnostics, by which you may discern and distinguish diseases, and in tra- cing out the process of each disorder, we shall point out the signs and circumstances, from which you draw a proper Prognosis, and infer the probabilities of relief or destruc- tion, the * prospects of life or death. Without such know- ledge you can never hope to attain any rank or standing in 24 the community or among your brethren; you can never hope to be regarded as enlightened or scientific Physicians. We shall endeavour to make you perfectly familiar with the several indications of cure as they present themselves in sketching off the minute history of each successive malady. But supposing you to be well informed by previous study of the qualities and properties of our numerous medicines, we shall rarely offer you any particular rules as to the choice of means for the fulfilment of these indications, except in some specific and important and well marked instances. For it is in this point more than any other that success depends upon the tact and adroitness of the practitioner, in availing himself of minute observations to be made only at the moment, and in bending to his purpose even the most unpromising of the materials in his hands. You will do well to seek for infor- mation on these slighter but not unimportant matters at the , bedside of the sick, in regular attendance upon the Hospital, and by assiduous and prying inspection into such other Clen- ical practice as you may have an opportunity of witnessing. You will at once infer from this brief sketch of the labours upon which we are about to enter, that in selecting the Me- dical Profession you have not chosen a life of ease and indo- lence. Be not deterred, however, by the apparent rough- ness and difficulty of the path before you. It will at every step become smoother and less tedious as you advance. It is consoling too to reflect that no doubt or' uncertainty hangs over your future prospects. Be but true to yourselves— urge into active and energetic effort the faculties of your minds ; be but diligent and persevering, and your success is certain. " Nothing," in our profession " is denied to well- directed labour," but remember that " nothing is attain- able without it." Finally, fix your attention upon the rich harvest which your ardent and enterprising exertions will enable you to reap ; look forward confidently to a life of use- fulness and benevolence—the grateful regard of the com- munity—the esteem of the wise and the good—a tranquil and honoured old age—the gentle whispers of a satisfied consci- ence—and the smiles of an approving God.