own understanding, than to wander after these ignes fatui of philosophy."

After a long and diligent scrutiny of Nature in this spirit, I have at last been enabled to place before the profession a Doctrine of Disease, and a Method of Cure, which, when the unity of principle of the one and the universality of application of the other have been fairly tested, will tend, I hope, to rescue physic and physicians from the obloquy and contempt with which the more thinking part of the public have too long looked upon both. In the course of these Lectures, gentlemen, it shall be my business to prove to you the UNITY OF IDENTITY of all morbid action, and the unity and identity of the source of power of the various agencies by which disease of every kind may be caused or cured. "The universe," says D'Alembert, "to him who should have sufficient comprehension to behold it at a single view, would only appear one great fact-one mighty truth." And in the same spirit Sir James M'Intosh observes, "the comprehensive understanding 'discovers the IDENTITY of facts which seem dissimilar, and binds together into a system the most apparently unconnected and unlike results of experience." Beware, then, of differences-of divisions; for as Lord Bacon well observes, "divisions only give us the husks and outer parts of a science, while they allow the juice and kernel to escape in the splitting." And from this you may learn not only the absurdity of nosological distinctions and differences, but also the utter nothingness and vanity of the many disputes that daily occur in practice, whether disorders resembling each other, and amenable to the same treatment, should be called by one name or another. In the language of Hobbes, "words are wise men's counters,―they do but reckon by them, but they are the money of fools, that value them by the authority of an Aristotle, a Cicero, a Thomas Aquinas, or any other doctor whatsoever."

More than twenty-three centuries have elapsed since Hippocrates distinctly announced the Unity of Morbid Action,-" Omnium morborum unus et idem modus est." THE TYPE OF ALL DISEASE IS ONE AND IDENTICAL. These are his words, and that is my Case.

was

That is the cause I am prepared to enter upon with as perfect a chain of positive and circumstantial proof in its support as ever offered to human investigation. Gentlemen, what Johnson said of poets is equally applicable to physicians: "The first, whoever they be, must take their sentiments and descriptions immediately from knowledge-their descriptions are verified by every eye, and their sentiments acknowledged by every breast. Those whom their fame invites to the same studies copy partly them and partly nature, till the books of one age gain such authority as to stand in the place of nature to another." It is in this manner that the descriptions of disease in our nosological systems have become a mere tissue of unnatural division, not to say of the most obvious contradiction; if the words in which they be conveyed have in many instances, any meaning at all. What, then, shall we say of reasoning founded upon facts which are no facts-upon mere assumptions which have no foundation in nature!

The schools of Egypt and Arabia, the eminent men of Greece and Rome, the great anatomical teachers and philosophers of the middle ages, knew not the circulation of the blood. How wild were their theories, how fanciful their hypotheses, may be gleaned from the fact of their naming certain blood-vessels, arteries, or air-vessels ;-tubes which you have only to wound, to see them pour out the living current in jets, were for ages supposed to contain not blood, but air! What innumerable fallacies must have entered into reasoning founded on such premises! Yet it was not till the seventeenth century that the illustrious Harvey demonstrated the true nature of the arteries, and the manner in which the blood circulates through the body. The more immediate reward of his discovery was calumny, misrepresentation, and loss of his professional practice. The same College of Physicians who, in after years, opposed the improvements of Montague and Jenner, made the Circulation of the Blood the subject of their bitterest satire. Not content with slandering the character of its discoverer, the more vile and venal of his medical brethren made it a pretext for declining to meet him in consultation. Harvey lived, nevertheless, to neutralise the malice of his enemies; he be

came successively the physician of the first two English kings of the Stuart race, James and Charles.

The more you can explain and facilitate the attainment of any science, the more you will find that science approach perfection. The true philosopher has always studied to find out relations and resemblances in nature, thus simplifying the apparently wonderful ;-the schools, on the contrary, have as invariably endeavoured to draw fine-spun distinctions and differences, the more effectually to perplex and make the most simple things difficult of access. "In universities and colleges," says Lord Bacon, "men's studies are almost confined to certain authors, from which if any dissenteth or propoundeth matter of redargution, it is enough to make him be thought a person turbulent.” Any exposition of the singleness of principle which pervades a particular science will be sure to meet the censure of schools and colleges; nor will their disciples always forgive you for making that easy which they themselves, after years of study, have declared to be incomprehensible.

The most perfect system has ever been allowed to be that which can reconcile and bring together the greatest number of facts that come within the sphere of the subject of it. In this consists the sole glory of Newton, whose discovery rests upon no higher order of proof. How was this discovery received on its first announcement? In the words of Dr. Chalmers, "authority scowled upon it; and taste was disgusted by it; and fashion was ashamed of it; and all the beauteous speculation of former days was cruelly broken up by this new announcement of the better philosophy, and scattered like the fragments of an aërial vision over which the past generations of the world had been slumbering their profound and their pleasing reverie." For upwards of ten centuries had the false philosophy of Aristotle enslaved the minds of civilised Europe, thus at last to perish and pass away! So that Time itself is no sure test of a doctrine, nor ages of ignorance any standard by which to measure a system. To Nature, eternal Nature, must Truth ever make her first and last appeal. By this, and this only, am I willing that the new fabric of medicine which I have presumed to

erect upon the ruins and reveries of the past, should be tested and tried. Till the world shall detect one real-one indubitable fact militating against the Views I am now about to develope, let not innovation be charged against me as a crime. Hippocrates, Galen, Boerhaave, Cullen, were all innovators in their day, nay, revolutionists in physic. The revolution I meditate, unlike those of some of my predecessors, is at least free from the imputation of being either painful or sanguinary in its character. The only agents it rejects are the leech, the bleeding lancet, and the cupping instrument. Let us now enter upon the developement of this NEW, but NATURAL SYSTEM.

Gentlemen, in the higher powers of Observation, Comparison, Comprehension, and Direction, termed Mind or Intellect, Man stands pre-eminent above all animals; in so far as regards the more immediate observation of certain things around him, he is nevertheless excelled in some respects by many. The eagle has a finer and farther sight; the hearing of the mole is more acute; the dog and the vulture distinguish odours wholly inappreciable by him; not a few of the wilder denizens of the forest have even a keener sense of taste and touch. In mere perceptive power, then, the beasts of the field are in some things permitted to surpass us; while the sagacity of the elephant and the dog, the courage and emulation of the horse, the foresight of the ant, the cunning of the fox, and the social and building habits of the beaver, declare to ushowever unpleasing the announcement—that others of God's creatures besides ourselves, possess the elements, at least, of that REASON, upon which we so highly pride ourselves. To the greater degree of complexity,—perhaps I should rather say completeness, of his CEREBRAL organisation,-to his more perfect developement of that source of all reasoning power, the BRAIN,-man assuredly owes this corresponding increase in the number and force of his reasoning faculties. The more complete mechanism of his prehensile organ, the HAND, gives him the power to execute what his HEAD conceives, in a degree of perfectibility that we look for in vain in the works of any other tribe of the animal kingdom. Look at "man's full fair front;"

it is a superadded-not a superfluous part; the more it diminishes and recedes, the nearer you will find its possessor to be akin to the brute. But, Gentlemen, the rudiments of every portion of this instrument of man's reasoning faculties,―—this directing Brain,variously developed, may be detected in almost every link of the great chain of animated beings of which he is confessedly the chief. To every variety of race that animates the globe, whether in external or internal configuration, we have undeniably many features of relationship; nor let us spurn even the meanest and most shapeless as beneath our notice—for of every organic production of their common Maker, Man, while yet in the womb of his parent, has been the type!—his fœtal form successively partaking of the nature of the worm, fish, and reptile, and rapidly traversing still higher gradations in the scale of organised existence, to burst at last upon the view in all the fulness and fairness of the perfect infant. But it is not in his outward But it is not in his outward form only that he passes through these various gradations of animal life. From Comparative Anatomy we also learn that each of his separate internal organs, on first coming into fœtal existence, assumes the lowest type of the same organ in the animal kingdom; and it is only by successive periodic transformations that it gradually approaches to the degree of completeness in which we find it in the new-born child. The heart of the embryo-infant is a mere canal, nearly straight at first, and then slightly curved, corresponding exactly with the simplicity of heart of insect life,—that of the snail, and other insects of the lowest Crustacea tribe, for example. And not the heart alone, but each and all of the several organs and systems of the body are brought to their perfection by periodic additions and superadditions of the simpler and more complex parts of the same organs and systems of the several orders of animals, from the least noble to the highest class of all-the MAMMALIA, of which Man is the head. Man, proud man, then, commences his fœtal life in reality a worm!—and even when he has come into the world, and has breathed and cried, it is long before the child possesses the mental intelligence of many of the adult brutes; in this respect Man is for a period

most of his sympathies and antipathies— his power of choice and resistance—the knowledge by Comparison, who is their friend, and who their foe,-Reflection, whom to conciliate, whom to attack; where to hide, and when to show themselves-the Memory of injury and kindness-Imitation, and consequent docility

in some instances, Simulation and Dissimulation, each pursuing its own mode of artifice? Do not their young, too, as in the instance of the child, gambol and play, and like it leave off both as they grow older, for other pleasures? And yet there are persons of a temper so unphilosophical as to deny them MIND! Does man possess a mental superiority over the dog greater, or as great, as the dog has over the oyster? Of mental as of physical power, there are gradations. If we have stupid and clever men, so have we stupid and clever animals, according to their respective races. But there are dogs that will observe, calculate, and act more rationally than some human fools you may see every day. When did you find the dog prostrating himself before a figure of his own making, asking it questions, supplicating it, and howling, and tearing his hair, because it answered him not? Which of all the Brutes quarrels with his fellow-brute for going his own road, whether circuitous or otherwise, to a town or village that does not concern the other in the least? Or which of all the animal tribes manifests such a paucity of intellect as, more than once, to mistake the same false signs for real sense,

imposture for integrity, gravity for wisdom, antiquity for desert? Never in my life, Gentlemen, did I see the dog or monkey implicitly submitting himself to another of his race in matters that especially interested himself. The monkey, for example, instead of trusting to the authority of his fellow-monkey, in a spirit of laudable curiosity, always handles with his tiny fingers, and examines with his quick prying eyes, everything that takes his fancy; in no single instance that I remember did I ever see him allow himself to be taken by the ears. Even in his language of chatter and gibber, he never seems to mistake the meaning of his comrades, never takes one sign in two or more senses,-senses the most opposite, so as to get confused and bewildered in his manner or his actions. Can you always say this of man? Have you never heard him, even in his discussions on this very subject, one moment charging everything of animal intellect to Mind, at another to Instinct,instinct which, to have a meaning at all, must mean this right action without experience, such as the infant taking its mother's breast as soon as born, or the chick picking up grain the moment it leaves the shell. True, the chick may mistake a particle of chalk for a grain of wheat, even as the infant the infant may mistake his nurse's finger for the nipple of his mother. Experience corrects the error of both; and this correction of error is one of the first efforts of the three mental faculties, Observation, Comparison, and Reflection. It is with these identical faculties that both men and animals perceive a relationship betwixt two or more things, and act in regard to such things according to their respective interests,-rightly in some instances, wrongly in others. The correction to-day of the errors of yesterday is the chief business of Man. As he grows in years, his experience of things enlarges, and his judgment as to their true value and relationship to himself becomes more and more matured. The Brutes, then, have the very same intellectual faculties variously developed, which, when stimulated to their utmost in Man, and with the assistance of his higher moral faculties, become GENIUS,-if by genius is meant the discovery of relationships in nature hitherto undiscovered, and leading,

as all such discoveries do, to practical results beyond cotemporary anticipation-Newton's system and Watt's steam-engine for example. Gentlemen, you now clearly see that in the power of gaining knowledge by experience,― call it Mind, Reason, Intellect, or what you please, the Beast of the field partakes in common with man, though not in the same degree; yet both partake of it in a degree equal to the particular condition and exigencies in which they are individually or socially placed. For animals, like men, have their cities and sentinels-their watchwords of battle, siege, and defence: nature, too, has given them all their respective weapons of offence and defence. Man, less gifted in either of these respects, first fashioned his sword, and his shield, and his armour of proof. It was only after the experience of centuries, he reached, by higher mental efforts, to the knowledge necessary for the construction of the musket, the cannon, and the other munitions of modern warfare. Necessity was the mother of his invention here, as, indeed, in every other instance; but by this also the lower animals profit. What but necessity enables our domestic animals to change their habits so as to live in peace, harmony, or slavery with man?-even as necessity obliges man enslaved to do and bear for his fellowman things the most repugnant to his nature. How different the habits of the domestic dog from the dog or wolf of the prairie, from which he originally sprang! In the wilderness, the one would all but perish for want, till stern necessity should teach him to hunt down his prey; the other would require stripes and blows through successive generations, before he could be taught like the shepherd's dog to come at his name, and to drive the sheep at his master's call, or arithmetically to single out from the herd two, three, or more, and watch or urge them on at his bidding. To deny animals mind is to deny them design, without which, putting mere instinct apart, neither men nor animals act in any manner or matter. The great DESIGNER of the UNIVERSE, in the creation of the first crystal, showed this. He proclaimed it when he made the sexes of the vegetable kingdom;----when, by the Zoophyte or plant-animal, he united the

vegetable to the lowest link of the animal world, he made his design still more manifest. When he further progressively developed his plan of insect, fish, and reptile life, and added the higher animals last of all, before he completed the chain with Man their master, he showed not only design, but Unity of Design; and when to men and animals he gave a power neither the crystal nor the vegetable possesses, -the power of following out designs of their own making,-he imbued them both with a portion of his Spirit-varying in degree, but to each he gave it in a measure equal to their respective wants and necessities. Deny this, and you deny God,-you deny God's works and words—words upon which the question of interpolation can never arise; for every leaf of every plant is a letter of His alphabet,-every tree a combination of the letters composing it, and every hill, valley, and stream-every tribe of men and animals-so many sentences by which we may perceive His will, and deduce His law. The stars, and constellations of stars, and their periodic motions, teach, even to our frail senses, the analogies which subsist in this respect between the motions of man's body and all the movements of Nature. In their harmony of design, they give us an insight into the UNITY of the ETERNAL. And we find embodied in them a principle by which we not only may know the past and present, but to at certain extent read the future, in its dim outline of twilight and shadow. In all humility, then, let us inwardly prostrate ourselves before the Omnipotent: but let us at the same time beware of that outward mock humility which too often leads to religious pride, and engenders anything but Christian charity; and let it rather be our delight to trace resemblances and harmonies, than to see in Nature only discords and differences. The world-the universe is a UNITY; and in no single instance do we find a perfect independence in any one thing pertaining to it. Betwixt man and the lower animals, we have traced link by link the chain of contiguity-mental as well as corporeal. Like them, he comes into the world, and like them, his body periodically grows, decays, and dies. When injured in any of its parts, it has similar powers of repair and reproduction. I know not why such powers

should be greater the further we descend the scale; but in the crab and lobster, whole limbs may be severed and reproduced; in the worm, the regeneration of half the body may take place; while in man, the highest of the chain, only limited portions of a tissue can be materially injured and recover. Disease, like death, is the destiny of all. To understand either aright, we must first know what Health is. In the state of

HEALTH,

an equable and medium temperature prevails throughout the frame. The voluntary and other muscles obey with the requisite alacrity the several necessities that periodically call them into action. The mind neither sinks nor rises but upon great emergencies; the respiration, easy and continuous, requires no hurried effort,-no lengthened sigh. The heart is equal in its beats, and not easily disturbed; the appetite moderate and uniform. At their appointed periods, the various secreting organs perform their office. The structures of the body, so far as bulk is concerned, remain, to appearance, though not in reality, unchanged; their possessor being neither encumbered with obesity, nor wasted to a shadow. His sensorium is neither painfully acute nor morbidly apathetic; he preserves in this instance, as in every other, a happy moderation. His sleep is tranquil, dreamless.

If we analyze these various phenomena, we shall find that they all consist of a series of periodic repetitions, each separate organ having its own particular period for the proper performance of its function; some of these phenomena are diurnal, some recur in a greater or less number of hours,—while others exhibit a minutary or momentary succession. At morn, man rises to his labour; at night, he returns to the repose of sleep; again he wakes and labours-at the appointed period he "steeps his senses in forgetfulness" once more. lungs now inspire air, now expel it—his heart successively contracts and dilates—his blood brightens into crimson in the arterial circle of its vessels-again to darken and assume the hue of modena in the veins. The female partner of his lot-she who shares with him

His