AS I consider this institution formed on the broad basis of universal good, the parent of general utility, not of selfish ostentation; and as this, with its sister kingdoms, may be justly stiled the emporium of medical knowledge, where many of its members, the brightest luminaries of the Hippocratic school, have not disdained to convey their discoveries to the world in the common language of this country — a language, if not esteemed so concise and elegant, yet full as comprehensive, full as replete with descrip­tive [Page 2]powers, as any of which Greece or Rome could ever boast; and as it must be allowed, that opi­nions in any art ought to be delivered in modes divested of all ambiguity and embarrassment, cer­tainly, considering our own vernacular language pos­sessed of these advantages, as being the most fami­liar to a very great majority of this audience, though learned, before which I have the honor to present myself, and perfectly understood by all — it will not, I hope, be construed want of respect, or a careless inattention to the consequence and dignity ever annexed to professional bodies thus associated, that I have presumed to deviate from some of my predecessors, dropping the tinselled trappings of Roman grace, for the plain, but more useful orna­ment of English perspicuity; and making use of a vehicle, easy, as common, to communicate my ob­servations, in order that I might, through the whole of them, be readily followed, and not in any part misunderstood.

For however familiar may be the Latin idiom to readers conversant in that language — however easy to comprehend in its nicest points — to au­ditors, not constantly habituated to that style of delivery, the familiarity, and ready comprehension, would be defective.

On these considerations I found some small claim to your approbation; and, considering the arduous­ness of the present undertaking, I flatter myself, I shall still farther experience your indulgence. Unimpressed with this idea, insurmountable indeed would have been the difficulties which presented themselves to my reflection; but conscious that liberality of sentiment, with men of erudition, directs the judgement, and softens the severity of criticism, every obstacle vanished, and diffidence gave way to duty. For it has ever been, with me, a fixed principle, and laid down as a law immutable; That, as every individual in the medical hemis­phere is so closely, and so necessarily united to the [Page 4]welfare of mankind, he is bound by the strongest ties, natural and social, to exert his abilities, how­ever weak, when called to promote any laudable purpose.

Connected therefore as I am with the members of this medical institution — with you, who actuated by philanthropy, make science the pleasurable labour of your lives — and that part of science your parti­cular study, the most noble which can engage the pursuit of man — framed by Divine Wisdom for the relief and preservation of the human species — preventing, mitigating, and subduing many of their corporal calamities — your wishes I considered as a mandate — and, as you have thought proper to elect me to this office of honor — an office, which would have been far better supplied by many of your associates — It became me, therefore, to re­flect, what there was in my power to offer, which might in some, though perhaps too small a degree, compensate for your loss of time and attention to [Page 5]the consequential avocation of your profession, which candour would subject you to on this occa­sion.

Conversant as you are with, assiduously engaged in, the acquisition of medical knowledge, and happy in the promulgation, two points fell only to my elec­tion; either to furnish something new, for the im­provement: or something to clear what might retard and clog the progress of the healing art.

Of the former, I fear, I have little to lay before you worthy of your attention; even vanity cannot suggest to, or persuade, me, that any thing has oc­curred to my observation, with which you may not, perhaps, have been long acquainted — My ani­madversions must therefore, in a great measure, be confined to the latter; wherein I shall only presume to offer some hints, which taken into the considera­tion of superior abilities, may assist, so am I led to hope, in extending our particular art to that goal [Page 6]of perfection, at which human exertions are limited only to arrive.

And, as many obstacles have been thrown in the way, which have prevented us from rising to that achme, as much as human endeavours, united with strong mental powers and indefatigable assiduity, judiciously conducted, would have accomplished; the greatest of which has been the thirst after theoretic knowledge — it might appear necessary to take a survey of the progress of the medic art, from the time of the divine old man, the first founder of sys­tematic physic, to the present aera, in which some possess no less merited, no less exalted characters. But to an audience like this, so well versed in the his­tory of physic, and all its branches, it would pro­perly be considered, a work of presumption and supererogation.

I shall therefore only, as it is necessarily con­nected with my subject, take a concise view of the [Page 7]means by which HIPPOCRATES acquired his know­ledge, extensive as it was, considering the period in which he lived — in the same manner, shew how his successors rather retarded than promoted the utility of the Aesculapian Art, particularly as some of our Professors steer not altogether clear of similar errors; and then attempt to point out, where some of our present modes require the aid of correc­tion.

HIPPOCRATES enriched his mind from observa­tion, and founded his practice on facts, simply as they appeared to him; who being blest with quick perception, nice discrimination, and profound saga­city, made such discoveries — deduced such certain consequences — and raised his superstructures on so solid a foundation, that he left behind him stupen­dous monuments of great abilities;— Abilities, so su­perior to his predecessors, and cotemporaries, that future ages pursued with avidity, and retained with confidence, many documents framed in the in­fancy [Page 8]of his art — and happy had it been for later times, had his plan, simple and easy as it was, been religiously observed. But, alas! Man, as if uncon­scious of his own weakness, vain enough to suppose he could discover the arcana naturae — investigate first causes — and carry his curious eye into the darkest labyrinths, began to prefer ingenuity to observa­tion; and mounted on the wings of false fame, dis­regarded the humble paths of modest inquiry, and built on vain and conjectural hypothesis;—and what the result? Theory arose after theory; and each succeeding one, though it corrected the errors of that which had been before adopted, still, like its predecessor, sunk into oblivion; leaving behind few remains worthy of practical pursuit.—

Nor is it difficult to account for the cause, why such different consequences awaited these different modes.

HIPPOCRATES, it is said, by the most rigid obser­vation of every action and motion of nature, of things [Page 9]which did in reality exist, acquired a wonderful know­ledge of the genuine disposition of Diseases; and by carefully comparing the same sort of distempers, and their various minute motions in different Pa­tients, and all the circumstances and accidents, which usually preceded, and attended them; he could readily foretel an approaching malady, and after its invasion give a right judgement of its pro­gress and event.

As Nature terminated diseases, when left to her­self, he observed her mode, first tracing the manner in which the symptoms, in those that were acute, succeeded one another; hence arose his art of pre­saging, and thus he formed his method of curing them, by imitating Nature when she proved herself defective.—From these observations, he discovered the use of Bleeding—Scarifications—Issues—Setons, where, in similar complaints, Nature supplied HAE­MORRHAGES, and ABSCESSES— Artificial Diarrhoeas, —Sudorifics—Emetics—Diaphoretics—Diuretics, &c. be­cause [Page 10]he found she, by some of these means, relie­ved the constitution under particular circumstances: hence then he became her humble imitator, con­scious, that she alone was the most judicious di­rectress.

But the Theorists, forming of themselves a set of principles, PRINCIPLES, the mere coinage of distem­pered reason, from them deduced all their arguments, supported all their practice, and endeavoured to prove Nature obedient to laws so founded.

Hence the incongruous, elementary, atomical systems of succeeding Sects — hence the conceits of an Helmont — the whimsicalities of a Paracelsus — hence a variety of chemical chimaeras, and all the inconsistencies of hydraulic, and mechanic subtlety; and hence fell medicine into shameful disrepute, it becoming more the pride of cavilling scepticism, and scholastic vanity, to build ingenious, though fal­lacious doctrines, than after detecting error, labour­ing [Page 11]to pursue Nature through her plain and humble paths.

And it appears astonishing to a reflecting mind, that notions so ridiculous, practices so absurd, should be countenanced in later times; when it is known, that all the labours of the ancients, as well as mo­derns, are chiefly valuable for the simple recitals they contain, founded on observation, collected from appearances, and delivered with candour: hence the praeeminence of an Hippocrates, Aretaeus, Trallian, Aurelianus, Celsus, Tulpius, Lommius, Morgagni, Sy­denham, and some others of more modern date; whom to mention, might be considered as indeli­cate, and the result of adulation.

And indeed this simplicity, the more it is pur­sued, the more strongly it convinces us of its uti­lity; affording the most certain, perhaps the only proper, method of acquiring, and communicating medical information. For the theories of the present [Page 12]day, though fraught with no small degree of plausi­bility, will not stand the test of critical inquiry; they all appear to be too generally applied, in fevers par­ticularly. —Can we suppose, that in such, as from their commencement to their termination are at­tended with profuse sweating, or a moist soft skin, a constriction of the cuticular pores takes place?— In those, where the circulation is languid—the action of the vascular system torpid—the prostration of strength sudden and extreme, that an active sti­mulus is the cause?—Or, in those where no oppres­sion, load, nausea, sickness at the stomach, or un­easiness in the intestines—no catarrhal or pulmonic affections manifest themselves, that they deduce their origin from too copious and morbid secretion of the mucus in those organs? Surely not. Yet, these, by different classes of practitioners, are con­sidered as the proximate cause of febrile affections, and applied in common to all.

But within these mansions, such a theoretic caco­ethes appears not to be nurtured. If we examine the nature of the proceedings within these walls adopt­ed, what is the roof, by which we are sheltered, but that of an AEDES AESCULAPIANA? If we advert to the public product of your application, what are your memoirs, so justly enumerated amongst the most valuable labours of the medic art, but the TA­BULAE AENEAE TEMPLORUM, ornamented by simpli­city, and supported by truth. ^*

Nor need we take up much time in furnishing proofs of the superiority of such a scheme over every other, which has been produced by the fertility of human invention.

View but our English Hippocrates, SYDENHAM; he, by recalling this mode, not only contended with, but conquered, a theoretic world, notwithstanding [Page 14]the powerful opposition he met with, invidious, as violent; and we find his descriptions stand at this hour unshaken, nor can be overthrown but by the hand of Heaven, when medicine shall be no more. So firmly supported are they by unerring truth; so simply, yet so justly, are they delivered; that they are to all intelligible — by all valued — by all quoted: even those, who, wild with hypothesis, leave nothing behind them but reliques similar to these, which can attract our attention, or merit our observation.

Still, notwithstanding we are convinced of the de­captive notions by which some of our early prede­cessors were governed — notwithstanding we can view the efforts of our cotemporaries not perfectly consistent in the application of their speculative opi­nions — notwithstanding the advantages, unknown to former ages, which daily are presented in every branch of medical philosophy; which are discover­able by slight observation, and may be truly arranged [Page 15]with the causae evidentes. We avail not ourselves of these advantages, or apply them sufficiently, to ren­der our modus medendi as perfect as it might be.

There is too great, too general a solicitude in searching after SPECIFICS, and inquiring into the nature of the semina morbi, as if the former did exist—or the latter were within the reach of human investigation. We seem to be more anxious about the AGENTIA MIRIFICA, than the AGENDA, as if the latter were completely understood; that they were is devoutly to be wished; for they come more ma­terially under our consideration; at least it appears to me a truth irrefragable, that were we to pay the strictest attention to the constitution, study more mi­nutely its parts, dependencies, moving powers and pe­culiarities, practice would be divested of many errors, with which it too unfortunately at present abounds.

However, that we may be enabled to prove the validity of this assertion, we shall attempt to shew [Page 16]THE FALLACY OF THE FIRST OF THESE PURSUITS— THE IMPOSSIBILITY OF DEMONSTRATING THE NATURE OF THE SECOND, IN GENERAL — and, THE REAL UTI­LITY OF ATTENDING CLOSELY TO THE THIRD, AND ITS MODE OF BEING APPLIED, in order to add to the improvement of the Art.

And, FIRST,

No idea, perhaps, has done more real injury, than that of Medicines acting specifically in conquering Diseases—Of this truth, a very superficial examina­tion will convince us: for it retards our researches in investigating their full and true powers — it pre­vents us, consequently, from extending those powers so as to be as diffusively useful as they might — it lays the foundation for a thousand deceptions; causing us to attribute particular consequences to ma­terials, which do not from thence, in reality, origi­nate, and keeping their true source hid from our ob­servation —nor is this all; it does worse — it often, by occasioning delay, increases the malady, reme­dies [Page 17]thus considered, are pretended to subdue, nay frequently generating disorders of a more delete­rious nature; overturning that first and salutary caution, which directs us in all our efforts, if we fail to do good, to do no harm.— ‘"Is artis medicae sco­pus est; ut hominem a tot gravibus malis liberet; ideoque Medicus nullo modo nocere, nedum Vitam destruere, aut Sanitatem laedere debet, utpote quum Medicina non nocendi, sed juvandi, sit Scientia."’ HOFFMANNUS.

Indeed the mischief ceases not here; it proves detrimental in another view; for it places the cre­dulous Philosopher, and Physician, on a footing with the impudent and ignorant Empiric, and too often throws such an odium on the Art itself, that Pro­fessors of the first eminence are frequently held in contempt, and treated with ridicule, by the injudi­cious and illiterate, who fly with confidence to the cabinet, and depend upon the presuming arrogance of every plundering impostor.

Still, strange as may be the appearance, painful the reflection to an informed mind, why should it be matter of surprize? Do not the Physician and Medicaster too often assign the same reason for their success, THE SPECIFIC POWER OF THEIR APPLIED AN­TIDOTE, and build on the same fortuitous exhibi­tion? And under such circumstances, the modest diffidence of the one can never, with the million, stand against the bold bustling ignorance of the other—for men of weak discriminating powers, of which nine tenths of mankind consist, at least if we confine them to medical understanding, will give credit to the opinions of creatures of their own level, and place, as Indians with their painted pa­gods, confidence in, and pay large tribute to, things their folly and superstition have set up.

But notwithstanding the credulity in this point of many professors of the art, Men held in the highest estimation adopting such ideas, handing them down to posterity, and having them received by succeed­ing [Page 19]generations—is it not singular, that not one spe­cific has ever yet been discovered, out of the num­ber which have acquired the appellation?

It has been, and is now, by some, thought due to the Bark in an intermittent fever—to Quicksilver and its preparations in the Syphilis; but in reality, even these merit no such distinction: for let us ask, Do they in all cases, as if possessed of specific power they would, become infallible? Or, will they by any means prevent the accession of these distem­pers? Practice proves the contrary; for they will not alone always cure these complaints—and men have been seized with intermittents whilst under a course of Bark—and the lues venerea with a mer­curiated habit.

As well might modesty and judgement be united to the names of M*******, G******, or any other empirical depredators with which this metropolis is loaded; as well might infallibility be added to [Page 20]every nostrum­monger, as specific powers in curing diseases, in all constitutions, to any medicine.

Indeed, if we search into the practice of men highly elevated in their profession, who retain such a species of absurd faith, we shall find such glaring contradictions—circumstances militating so diametri­cally against, and so totally subversive of these opi­nions, that we must be convinced of the fallibility of such a dogma.

For it is not uncommon to have accounts pub­lished by some of the efficacy of a medicine in cer­tain complaints, which cures, they tell us, SPECIFI­CALLY, to which are tacked a long catalogue of cases in proof; whilst at the same time, in the hands of others of equal eminence, tried under similar cir­cumstances, no such surprizing effects are manifest­ed. Need I, to what I have already mentioned, add the accounts of arsenic, hemlock, deadly night-shade, henbane, flores cardamines, flores zinci, fossile alkali, [Page 21]and some others, which have been foisted upon the world under such a pretence? All having work­ed miracles under the direction of some, whilst others have failed in the administration.

To what are we to attribute this diversification? Can we dispute the abilities of the authors? It would be considered presumptuous.—Can we doubt their veracity? It would be thought illiberal.—Dare we think they are attempting to acquire same from false principles? It would be construed invidious.

What are we to conjecture? Certainly that no such specifics exist; and that those who were fa­vourers of such an opinion, unwilling, or unable to pursue their researches, were happy in having so easy a support to rest upon; or, uninclined to lessen their consequence, by receding from sentiments once adopted, and publicly sanctioned by their fiat, con­descended to suffer science to be cloathed in an unintelligible jargon, and lead men, credulous as [Page 22]themselves, to believe it was impossible to proceed farther, pleased as well with the phantom, as the reality of knowledge. Hence was a check given to particular inquiries, by implicit confidence being paid to hoary-headed obstinacy, I had almost said, cunning, creeping under the cloak of false expe­rience: hence was the healing art impeded in its progress by such a belief; and hence a few charac­ters called great, made thousands appear little, and live in the shade of indolence and obscurity.

Examine but the works of Galen, Diascorides, Oribasius, Messuë, Boerhaave, and almost all the wri­ters of the Materia Medica of former ages, and compare them, with what has been written by some of the latest authors, who have made real experience the test of their opinions, you will find, that a multiplicity of errors, from time to time, have been transmitted from one to another, forming a con­temptible farrago of specific absurdities.—View but the imaginary powers bestowed on BEZOAR and SAF­FRON, [Page 23]two out of the numberless instances, which might be produced. What mighty virtues have not been attributed to the former, by men renowned for medical sagacity? So multifarious, so efficacious, that almost all powerful medicines, or, those ima­gined such, were called Bezoardics; and what from faithful experiment is it now proved? one of our most imperfect absorbents.

What has not been said of Saffron? Receiving for its supposed amazing specific powers, the pom­pous names, Aroma Philosophorum—sanguis Herculis— Rex vegetabilium—Panacea vegetabilis—hortus Laetitiae— medicina Tristitiae—and many more, given in small quantities. Indeed the great BOERHAAVE considers a few drops of the extract of Saffron, inspissated only to the consistence of oil, and taken in a glass of rich wine, as highly exhilarant and cordial. How different from the experience of this day! for ex­cept in very large doses, saffron is not known to [Page 24]produce any effects, and of these accounts are very rare and doubtful.

But as an apology for this credulity, might it not be called fanaticism? It has been asserted, that the means, by which medicines produced their effects, at least those to which were attributed a specific power, were impossible to be detected and account­ed for; and indeed the same notion is too prevalent at this day, in many cases. To such a height is it carried, that an arcanum scrophulosum has been pro­posed even to the members of this Society; so fla­grant is folly in her attempts, yet meets, neverthe­less, with such enormous encouragement; and, though associated with ignorance, and supported by presumption, is so successful, it is no wonder that crude inexperience should be led to conclude he might palm his nostrum on this Institution; for great medic characters, so called at this time, we have seen swell the catalogues, and enrich the lists of great Impostors.

However, to prove the fallacy of this opinion, let us examine one medicine, which has long been held replete with specific power, and which claims more the title, could such be allowed, than any other medicine with which we are acquainted, if we ex­cept Quicksilver; we shall by that means detect the errors accruing from such an idea, and perceive the benefits arising from the discovery of its true action —Benefits, which should stimulate us in all cases to similar inquiries: I mean the BARK.

This was long considered to cure Intermittents specifically—that is, we know not how—by some la­tent inexplicable power; and indeed such was the confidence placed in this miraculous drug, so thought, incomprehensible as astonishing, that in cases of this kind, it was indiscriminately exhibited—though very often productive of great mischief—till from long continued, and often repeated trials, some of the more judicious observers found, that this specific power was not always in Intermittents an inoffen­sive, [Page 26]much less a certain curative agent, not even of the same complaint at different times in the same person: hence it became necessary to inquire, from whence this deviation arose, and in which state of the complaint it might be productive of the greatest success; and it appeared to be when the constitu­tion had been harrassed, and the vascular system so far oppressed, as to be debilitated by the preceding malady, or was, ab initio, in that state—For given at first, when the constitution was in full vigor, it pro­duced very dangerous effects, converting quotidians, and tertians, into continued Fevers, aggravating, in­stead of alleviating the febrile symptoms, and form­ing a variety of other distressing consequences.

On considering these phaenomena, it was manifest, that what was thought its specific power, depended upon some exertion which occasioned the system to act, under some circumstances, with too much force, by increasing the vascular tone.—Hence men, imbi­bing this idea, laboured to abate the activity of the [Page 27]constitution, by bleeding, purging, &c.—or suffered it to be weakened by delay, before they exhibited this medicine, which was then almost always suc­cessful, unless prevented by some constitutional de­fect, that at the same time required for its allevi­ation or subduction some attention.

It appears therefore obvious, that the virtue of this medicine lay not in its correcting or destroying the miasma, or virus, producing the Intermittent, but in the exertion of its tonic power; hence a peculiar state of the constitution was necessary,—and hence the necessity of knowing that state before we can promise success.

Thus we see the particular power of this univer­sally allowed specific was developed, by observation and experience; and there remains no doubt of the Bark producing generally, I might have said always, the disagreeable, and sometimes dangerous effects above specified, if given too early, or persisted in— [Page 28]without it brings on some debility at first, as it some­times does, by becoming purgative: and it may be laid down as an invariable rule in practice, that where there is in the habit strong vascular action, and an inflammatory diathesis of the blood, which are, I take it, generally conjoined, Bark universally does harm, —where the contrary constitution is prevalent, uni­versally good, if no topical defect impedes, or coun­teracts its action: nor does the Bark being successful in some local inflammatory complaints, at all inva­lidate the force of the argument; for in those cases, the disorder itself is not an active, but a passive in­flammation.

Similar arguments might be adduced to the same purpose, proving the known action of Quicksilver, and its saline compounds, capable of producing its good effects, instead of its imaginary specific powers, and of some others. But what I have advanced will, I hope, prove sufficiently satisfactory to shew, that by this idea of medicines acting specifically, no small [Page 29]impediment has been thrown in the way of medical improvement: for men, satisfied with this LUSUS, this LARVA RATIONIS, practised from principles falsely founded, nay, very often, without any principles at all —occasioning great loss of time, and not only doing mischief by injudicious application, but keeping the extensive powers of many active medicines immersed in obscurity. Hence, those formerly administered in one malady only, to which their specific power was supposed to be singularly adapted, we now find, their modes of action being brought to light, in a variety of others extremely useful and inesti­mable.

Yet it is very extraordinary, that men flying from inquiries after properties it may be in their power to discover, should rush forward in pursuit of what lies far beyond their reach, the NATURE OF THE SE­MINA MORBI, the second point appropriated for dis­cussion.

That such an attempt should be made in the early periods of an art, while the professors were almost totally ignorant of the nature of the human ma­chine, with regard to its moving powers, and sym­pathic affections—knew little of the animal oecono­my—of what different parts the body was formed; how they were actuated by each other, and by what laws they were governed—at a time when philoso­phy was searching after the Principia Rerum, is not to be wondered at.

But, considering this inquiry has been set on foot ever since the prevalence of Hippocrates' idea of the ‘" Calidum & salsum;— Calidum & acidum;— Calidum & amarum, & alia innumerabilia:"’ a period of above two thousand years, and has ever continued in the same point of uncertainty. Is it not surprizing then, that men should for ages perplex themselves in the attempt to make discoveries, so much above the power of human understanding?—that they should vainly dissipate their time in endeavouring to detect [Page 31]the component parts of materials, which are in gene­ral too minute to be collected—in all, too subtle to come within the limits of man's scrutinizing abilities?

Knowing these things, is it not still more asto­nishing to hear men talk of the acidity and alkales­cency of the materies morbi; and otherwise speci­fying the particular nature of the acrimony, pro­ductive of eruptive complaints? to assert positively, that the venereal virus is an alkali, and propose to cure disorders from that cause with muriatic acid, traversing through all the diversified mazes of the human body, and there making neutral salts by the specific combinations?

Yet, ridiculous as is this attempt; fantastic this enthusiasm, some modern anatomists hold up the certainty of such discoveries, and form from thence schemes of practice, curable and infallible, implant­ing in young inexperienced minds, an IGNIS FATUUS, unprofitable as visionary.

Let Philosophers of such a description go in quest of atoms, and the diversified modification of matter, mount air balloons, seek medical knowledge in the clouds— Astra petant, quomodo formentur,—be it ours to inquire how the effects produced by matter, in its combined and morbid state, are to be remedied, and to such heated imaginations be the advice of CELSUS recommended.— ‘"Rationalem quidem puto medicinam esse debere; instrui verò ab evidenti­bus causis; obscuris omnibus, non à cogitatione artificis, sed ab ipsâ arte rejectis."’—Advice, so pregnant with unerring truth;—fraught with such strong conviction, that on this point it is needless to dwell any longer—the futility of such inquiries—the impossibility of attaining the quid desideratum, are so conspicuously evident to the eye of common sense, primâ facie, that they need no arguments to be ad­duced in proof. For what understand we more of the particular nature of the virus creative of the Plague—Small Pox—Pemphigus—Cancer—than [Page 33]the first observers of these diseases?—Virus, which might be examined, if any could, from the copi­ousness of the matter produced: but we, like them, form our judgement only from the effects.

It will be more to our purpose to examine how much greater benefit will be derived to mankind, by paying attention to that, upon which, to be of any service, our applications must act; for certainly the human machine itself is the grand object of the Physician's consideration; and the moving powers of that instrument, with what I shall, for the present, call their appendiculae, the things which require his attention, and which being too much neglected in our descriptions of cases, has retarded, and still re­tards the progress of the healing art.

By THE MOVING POWERS, I mean the muscular Fibres and vascular System possessed of Irritability— the nervous System of Incitability— and the sangui­nary [Page 34]mass of Fluids, of the Vis animans & servans Naturam.

By the APPENDICULAE, the Lungs, Stomach, Intes­tines, Uterus, Kidneys, &c. parts which, affected, have some influence on the moving powers, with respect to their action. The Brain, and Heart I include in the nervous and vascular system.

By the incitability, as applied to the nerves, I would be understood that power which is capable of being put into action by immateriality, such as mental affection—sympathy; though it may be put into motion by material stimulus; to which Irrita­bility, itself abstractedly considered, is only obedient; though that may be also rouzed by the connection of parts, wherein it resides, with the nervous sys­tem, and by means of the nerves thus put into ac­tion, and supported.

But, in order to form a proper idea of what I mean for your consideration, I must beg leave to take a survey of the machine, according to my di­vision, in the enjoyment of perfect health.

Now in this case, the principles of which it is formed, must be in a state exactly, or pretty nearly proportioned to each other; so that one may assist in promoting and supporting the vigor of the other, and producing those effects with ease, and constancy for which they were ordained.

The moving solids of the human machine must have such firmness, pliability, and elasticity, as to enable them to answer to the impulse of the given Irritability.

The Irritability of such a nature as to be kept in action by the nervous incitability.

The nerves to be so formed, as perpetually to supply their power, when and where wanted, with regularity.

The blood and fluids in such quantity, and of such consistency, as to receive the vis animans, re­tain and transfuse it through the whole system in an invariable current—and so bland, that they may produce no defect in the secretory or excretory or­gans, so as to impede them in their duty.

And the Appendiculae, so complete in their pow­ers, that they may perform their actions to which they are allotted, with constancy and freedom.

While matters are thus conducted, the machine remains in perfect health; but if a defect arises in one or more of these particulars, diseases succeed in proportion to the magnitude of the defect—and of different natures, agreeable to the parts affected, and their connections, and the changes brought on [Page 37]in them, which may be either partial or general, or idiopathic or symptomatic; and the cause of such defect will arise from the imperfections, in some of the sources, from whence the active powers deduce their origin, immediately or secondarily. And as we conclude, that the sources of all activity, are either the brain, medulla spinalis, heart, or blood— so in some of these we shall find something contrary to a state of nature, in its most perfect form; or a derangement in some of the appendiculae, by which these sources are disordered.

But that I may be more perfectly understood, I shall trespass only a very little on your patience, to supply two or three short, though common, cases, by way of elucidation.

Suppose a man of strong stamina—great vascular irritability—strong equable nervous incitability, abound­ing with blood, copious and tenacious, has perspiration obstructed by what is called CATCHING COLD. We [Page 38]are all acquainted with the general result. The mat­ter which ought to pass off by the perspirable pores, is retained in the habit; the vascular system expe­riences a plenitude—a quick circulation is produced— Irritability increased—and febrile symptoms succeed: here the immediate source lies in the heart, and vascular system, excited by a stimulus from the oc­casional cause, constriction of the cuticular pores; and that by the more remote, the application of cold;—and if there should be in such a constitution, any defect in the brain, lungs, &c. or any other in­ternal organ, or part, a topical affection will be the consequence of the inflammatory kind, which will increase and support the fever; or should any of the organs be affected in the first instance, that af­fection will occasion the same effect; and this arises also from the source above specified.

But should the remote cause operate on one, of a weak—relaxed habit—possessed of quick nervous incita­bility, but a small portion of vascular irritability, and [Page 39]a thin sate of fluids, with a paucity of blood; the consequences will not be so violent—The febrile af­fections will be of the slow kind, attended with more nervous symptoms, the pulse will be quick, but languid; the heat in a small degree increased, but not so permanent, accompanied by spasms of various parts; depression or sinking of the spirits, and seldom any topical inflammation—here then the nervous system will be more affected, discovered by the languor of the moving powers, load, and hea­viness of the head, coldness of the extremities, and such other symptoms, as indicate THE SOURCE OF MOTION, the nervous System, the part oppressed.

But suppose, lastly, a Man of good stamina, with a weak vascular Irritability, tho' steady, nervous Inci­tability, and Blood of a tolerable density, and in mode­rate quantity, under the present circumstances—what will from thence occur?

The circulation of the Blood will not be so greatly accelerated, as in the first instance—the ex­tremities will be cold—the perspiration obstructed, though not in so great a degree—uneasy sensations of coldness, and heaviness of the head—disturbed and restless nights—oppressions on the praecordia— chillness, and flushings of heat not continued, or regular—dejection of spirits—and affections, some­what approaching to delirium.

Thus we find, from the same immediate cause, different effects will be produced; and they may be varied, as the different combinations in the consti­tution happen—and we must to this add, as the blood and fluids are in such a particular state to re­ceive the vis animans more or less copiously, or to transfuse it more or less freely, the effects may be increased or diminished in a proportionate degree— or as it may be, more or less acrimonious, for acri­mony always adds a stimulus, particularly to the vascular system. Though some may exert at the [Page 41]same time as a sedative power on the nerves, and therefore the additional stimulus not be so percep­tible.

Besides, we know that the intestines, lungs, liver, kidneys, bladder, uterus, &c. have such universal connections with the whole machine, particularly the two former, that they can in many instances transmit their affections sympathetically to the whole, or some parts of the body which lie at a distance; hence then, as they are more or less affected, so will be the moving powers in adequate proportions: in­stances of which are observable in some symptoma­tic, inflammatory, catarrhal, hectic, remittent, ver­minose fevers, &c.

Now, as is the nature of the moving powers; as are the different combinations; as is the state of the fluids, with respect to their acrimony or blandness, texture, and capability of receiving and transfusing the vis animans; as is the state of the appendiculae [Page 42]and muscular stamina, so do constitutions vary, and so are different effects produced by similar causes; which we see often occur in epidemic, and other complaints, where, though the leading symptoms may be similar in a great degree, the concomitants will be different, and put on various appearances, as we find in the recitals of the same complaints by different authors: hence arise many of the species and varieties of different genera of diseases; hence a deviation in our modus medendi, and hence the good effects of one medicine in some instances at one time, which produce no such benefit at another, in complaints considered as similar: and hence, per­haps, also arise the good or bad effects of the same medicine given in different doses, and likewise the necessity of forming different combinations to make it act with certainty and success in different consti­tutions.

Let us, therefore, take a survey of the effects of medicines in different doses, or differently com­bined, [Page 43]and see what conclusions we may from thence deduce.

Opium, in full doses, instead of proving anti-spas­modic, anodyne, or narcotic, has often created other distressing symptoms; and so far from taking off spasms, alleviating pain, or procuring sleep, occa­sioned nausea, vertigo, and restlessness, whilst in smaller doses it has procured every desired purpose.

Mercury also, given in a similar manner with re­spect to the dose, has also occasioned disagreeable consequences, instead of affecting the salivary sys­tem, its chief scene of action, producing nausea, gripings, and bloody stools, whilst in smaller doses, it has readily been absorbed into the habit, and gra­dually brought on a ptyalism, nay often cured with­out any perceptible effect.

Under the same circumstances, Bark has been the cause of sickness, purging, and constantly rejected [Page 44]by vomiting; producing not any of its salutary ef­fects, either by prolonging the apyrexy, or taking off the febrile affections, which have been accom­plished by cold or hot infusions of this medicine.

On the contrary, small doses of these very ac­tive materials have been productive of no sensible or curative effect sometimes, whilst administered in larger doses, their good consequences have been made manifest.

And again: It is indisputably true, that these medicines given in any quantity or form, they may, the most perfectly agreeable to the constitution, and without having any painful concomitant circum­stances attendant, have by ho means answered the desired purpose; but being joined with other reme­dies, have proved successful.

What then can be the cause of these deviations? Is it in the medical ingredient itself? Impossible— [Page 45]For every medicine considered in itself, ceteris pa­ribus, must always be alike; its action must be in­variably the same; and in similar constitutions, or in the same constitutions under similar circumstances must universally produce the same effects.

Though I am well aware it may be urged, that the same medicine in the same person has appeared to act, as if it varied its mode of action; this will be readily granted—but then it has been owing to some change brought upon the habits by illness, in­discretion, or some other cause.

For medicines producing in a state of full health one effect, will create others in a state of illness, with respect to the constitution; though the action of the medicine must be the same.—For the consti­tution labouring under an indisposition, its powers are altered, they act not under a state of healthful nature, but require something to relieve and regu­late them—Now the same medicine which relieves, [Page 46]and regulates them, during the illness, would, when the illness was conquered, and the powers of the constitution returned to their natural order, or stan­dard, produce bad effects if continued, inasmuch as the same action of a medicine in illness, producing the same effect on the habit, brings that habit into a state of health by that very action; which action, the body being in an healthful state, is too power­ful; for it then needing no such aid, would have its powers too much increased, and by that means distress from that very source would be occasioned. —The same argument may be made use of, where debilitating means have been applied, in order to reduce the too active powers of the habit, morbidly affected.

From what has been advanced I conclude, there­fore, that the cause of these deviations depend solely on the state of the constitution, and by no means on the nature of the medicine.

Now, as I consider the action of medicines, and the semina morbi, to be exactly under the same point of view, regarding their respective operations on the machine, and effects produced—I say, these depend totally on the nature of the constitution operated upon—for instance,

If a Man of strong stamina, great vascular irrita­bility, steady, regular, nervous incitability, firm texture of the blood, was to be seized with an intermittent fever, of the quotidian or tertian type, from marsh miasma—in order to form his cure, the vascular ir­ritability must be abated, the too strong tone of the solids, and muscular fibres in some degree debilita­ted, and the cohesive power of the blood weaken­ed—by bleeding, purging, cooling, saline medicines, antimonial diaphoretics; — which done, the Bark might afterwards be administered. And if a man of a similar constitution takes so large a quantity of heating stimulants as to produce the same febrile appearances, without intermission — the treatment [Page 48]would be the same.—Not from the miasmata, or stimulants, having produced these effects—but from the same constitutional causes.

But was the marsh miasma to affect a man of de­bilitated habit, weak nervous incitability, and enfeebled vascular irritability, with a loose texture of the sangui­nary mass—cordial, nervous medicines with the use of blisters might be added to the use of the Bark; and these would be required from constitutional causes also,—that the constitution itself might be rouzed to feel the tonic power of that remedy, and experience its good effects.

A variety of other instances might be offered in proof of the same positions—and this mode of rea­soning will be found applicable to almost all cases; particularly, all such as are general in the habit, or are owing to general affections: and the more it is examined into, the more the propriety and neces­sity of paying particular attention to what has been [Page 49]specified will appear; but what has been said will, I hope, be sufficient to supply the proposed hints, and lead me to my last proposition.

‘" That one present source of retarding the progress of the medic art, is the loose and neglectful manner in which cases and their modes of cure, or want of success, are described."’

It has, I flatter myself, been clearly proved, as far as the time allotted upon this occasion will per­mit, that the constitution, with its different divisions, require the first attention of the Physician; and it will readily occur, that in practice it is to be con­sidered not only collectively, but abstractedly; that it should be found out in what part the constitution is most defective, whether respecting its nervous In­citability— vascular Irritability — muscular Strength — texture or composition of the Blood—and Fluids—and the Appendiculae.

For as all the parts act in combination with each other, as they transmit to each other the principle of their power, yet may experience separate affec­tions inherent in themselves, which may be gene­rally or partially communicated, creative of general or partial disturbance — they should always be par­ticularly attended to: inasmuch as the neglect of some, may occasion too often our endeavours to be­come abortive.

But we find commonly too little said on the pre­valent peculiarities of the constitution, upon which different medicines have been tried in similar dis­eases, wherein they have sometimes proved success­ful, sometimes otherwise.

Now, as medicines act differently in different quantities—with different combinations—in diffe­rent constitutions—in the same constitutions at dif­ferent periods — in the same disease at the different times of the malady, with regard to the good or bad [Page 51]effects they produce — and as this apparent diffe­rence of action depends upon the different states of the moving powers, and what I call their appendi­culae, the constitutional peculiarities should always be nicely discriminated.

This mode would often enable us to discover, on what account various remedies had been successful; wherein they had failed, and direct us to the best method of selecting and combining medicines, and of curing diseases, such as fall immediately under the Physician's care; and assist, in most, to which the Surgeon lays claim, as little, very little is to be done with the semina morbi, and the specific power of our remedies is merely ideal. For as is the state of the moving powers and fluids, with their combi­nations, so will be the action of our medicines, and consequently so will be the indications in our appli­cations.

Permit me, before I conclude, to offer a case, by way of exemplification, which will afford, I presume, no weak proof of what has been advanced.

Mr. *****, a person of middle age, had been some time afflicted with a disease, similar to what is termed GONORRHAEA LIBIDINOSA.

His muscular stamina were tolerably good; he had a great deal of nervous incitability; weak vas­cular irritability; the texture of the blood not firm, nor could be called broken; his digestion, tho' his appetite was tolerable, defective; he had now and then chilliness, succeeded by flushing heats, which came on irregularly; his pulse in general was slow, and undulating; and when quickened, as it would now and then be, on some extraordinary occasions, weak; his viscera all appeared found; ^* [Page 53]his bowels very irregular, sometimes extremely cos­tive, at others as much the reverse—always in one extreme or the other; his urine pale, and limpid for the most part, but now and then depositing a whi­tish, furfuraceous, mucilaginous sediment — he was petulant, and irascible when trifles perplexed him; when not, timid and despairing—his fluids were acri­monious; his memory weak, and his recollection painful; creative of much uneasiness, when he could not bring to his mind that of which he was in quest —his whole frame was in general so languid, that slight motion greatly fatigued him; his extremities were in general cold — in easterly or south-west winds he always complained of being worse, and was perceptibly so — his nights were constantly rest­less — he had sometimes two or three emissions in the night; complained of partial heat at the lower part of the back, which he said, now and then, trans­fused itself all over him, and made him extremely faint—he was never thirsty.

In this state he had continued for ten months, though now visibly growing worse, and had been under the care of two physicians of eminence: they had put him under a course of restringent medicines — bark, white vitriol, ginseng, &c. and ordered him the cold bath; but all proved inef­fectual.

At this period, his constitution was considered in general after the mode above recommended; taking in also the topical affection—a weakness of the se­minal vessels, and determination of the fluids to those parts creating heat, and causing emissions.

The INDICATIONS OF CURE were,

To determine the Fluids externally, by increasing Perspiration — to strengthen the digestive Organs — in­crease the Irritability of the vascular system — abate the nervous Incitability — and give tone and firmness to the habit in general, which were accomplished by cor­dial saline diaphoretics, warm tonics, camphorated [Page 55]and aethereal anti-spasmodics, and stomachic bitters —keeping the body moderately and gently open by mild aperients.

Under this method, his extremities first lost their coldness, in a great degree, and when warm, he always found himself relieved; at which time there was a great itching in his skin, which was distend­ed, appearing like an universal essera, the matter by a general stimulus under the skin, elevating the whole surface regularly, not shewing any eruptions, except here and there, one now and then, on his breast, or on the lower part of the head, just above the neck, at the roots of the hair. He began now to recover every day, and when his system shewed it was in some degree invigorated, bathing in the Thames and riding exercise established his cure.

The reason why the former Gentlemen had been so long unsuccessful, appears very obvious: they had not paid any attention to the torpid state of [Page 56]the vascular system, on which account the fluids were always crowding upon the internal parts, ha­ving their acrimony increased; and the astringent medicines, not being capable of exerting their ac­tion, from a defect of vascular irritability, the ves­sels being in such a state of torpor, as not to feel the effects.

Hence the seminal vessels, being before in a wea­kened state, suffered a partial irritation, by the fluids there collected, occasioning stimulus, and in­creased heat — emissions succeeded emissions — the machine became more and more debilitated — the nervous incitability increased; the consequence of which would soon have been a hectic fever with a tabes.

Would time permit, a variety of cases might be adduced, in which similar success from similar rea­sons have confirmed the validity of a practice so founded — and I am fully persuaded, that in all our [Page 57]recitals of cases, whether successfully or unsuccess­fully treated, were we to advert to what, perhaps, by some may be considered as minutiae too trifling in the present scale of physic, we should find, as well from one as the other, much useful matter proceeding—And I have no doubt but we should discover, in very many, if not in all, the reasons why accounts so similar in their descriptions, so dis­similar in their consequences, have, and do present themselves daily to our view.

But I flatter myself, what has been already ad­vanced will be sufficient to afford hints, that may induce some more capable to attempt the investiga­tion, and give still clearer views than lies within the compass of my very limited knowledge: I shall, therefore, conclude in the words of a favorite au­thor, as they are expressive of my wishes— ‘"Non dicam, quod ad commodiorem & certiorem me­dendi methodum nihil exinde inveniri possit. Doc­trinam itaque, quemadmodum cum praxi cohaereat, [Page 58]& quae utilitas in certam & compendiosam medendi methodum inde redundet, non hominum ad judi­candum ineptorum, non juvenum &c in praxi planè inexercitatorum, non sectariorum, & qui veras de­monstrandi, & logicas regulas ignorant; sed ves­tro, VIRI SOLIDISSIMA PERITIA ET ERUDITIONE IN­STRUCTI, judicio, candori, atque integritati, nec non attentiori meditationi atque experientiae etiam atque etiam commendo."’