If medical works have been wanting in facts, they have abounded in theories.

Dr. James Graham, the celebrated Medico-Electrician, of London, says of medicine, "It hath been very rich in theory, but poor, very poor, in the practical application of it."

Dr. Jacob Bigelow, Professor in Harvard University, says in his annual address before the Medical Society, in 1836, "The premature death of medical men brings with it the humiliating conclusion, that while other sciences have been carried forward within our own time, and almost under our own eyes, to a degree of unprecedented advancement, medicine, in regard to some of its professed and important objects, (the cure of disease,) is still an Ineffectual Speculation."

It is almost universally believed that the science of medicine, as taught in the schools of physic, and practiced by the regular faculty, is based on established principles,--principles that have been handed down from generation to generation, that are as demonstrable as those of mathematics, and that a man who has studied three years, is prepared to practice Scientifically. If this were the case, it would save us the necessity of writing this little volume, as the literary world groans under the weight of medical works that have been thrown upon it the errors of which, each succeeding author has proved to be as numerous as its pages.

At what age of the world medicine for the cure of disease was introduced, history does not inform us. Frequent reference is made in the bible to leaves for the healing of the nations, the plant of renown, and to various other botanic medicines; but we have no account, in that book, of mineral poisons ever being used to cure disease. Such an inconsistency, sanctioned by it, would have placed in the hands of the infidel a more powerful argument against its truth than now exists.

At whatever age disease may have made its appearance, the first man whose writings on medicine have descended to posterity in any thing like a respectable shape, is Hippocrates, born in the island of Cos, about 460 years before Christ. Supposing himself descended from the ancient and fabled Esculapius, he devoted his mind assiduously to the healing art. He examined attentively the opinions of others, thought and judged for himself, and admitted only those principles that to him seemed founded on reason. As a theory of life, he advanced the doctrine that the body is endowed with a semi-intelligent principle capable of applying to its own use whatever is congenial with it, and calculated to improve and restore it; and of rejecting and expelling whatever is noxious, or tends to the generation of disease.

He believed in the conservative and restorative power of nature, when its laws were strictly followed, or aided by suitable remedies. Hippocrates studied diligently, and almost exclusively, the great book of nature, instead of the visionary theories of men, and probably adopted a more correct theory, and safe and successful practice, than any who succeeded him, until the time of Thomson.

Claudius Galanus, or Galen, was born in Pergamos, in Asia Minor, A. D. 131. He depended on innocuous vegetables; sometimes simple, generally very much compounded; and his practice was so successful as in many instances to be ascribed to magic. The theory of Galen was the acknowledged theory of medicine until about the time of-Paracelsus who was born in Switzerland, in 1493. He appeared as a reformer of the system of Galen, rejecting his safe botanic treatment, and administering, with a bold and reckless hand, mercury, antimony, and opium.

Notwithstanding thousands were destroyed by this reckless quack, his practice has been handed down to the present time, undergoing various changes and modifications. Says Professor Waterhouse, "He (Paracelsus) was ignorant, vain, and profligate, and after living the life of a vagabond, he died a confirmed sot. He studied mystery, and wrapped up his knowledge in terms of his own invention, so as to keep his knowledge confined to himself and a few chosen followers." It appears by Prof. Waterhouse, of Harvard University, that mercury, antimony, and opium were introduced into common practice by Paracelsus, who was the chief of quacks, which remedies continue to the present day to be the most potent and commonly used by the faculty.

Stahl, a native of Anspach, rejected all the notions of his predecessors, and has the credit of undoing all that had been done before him.

Hoffman, his contemporary and friend, supposed life dwelt somehow or other in the nervous system.

Boerhaave, a native of Holland, selected from all the preceding writings whatever he deemed valuable, preferring Hippocrates among the ancients, and Sydenham among the moderns. This celebrated physician and scholar ordered in his will, that all his books and manuscripts should be burned, one large volume with silver clasps excepted. The physicians flocked to Leyden, entreating his executors to destroy his will. The effects were sold. A German count, convinced that the great gilt book contained the whole arcanum of physic, bought it for ten thousand guilders. It was all blank except the first page, on which was written,-- "Keep the head cool, the feet warm, the body open, and reject all physicians." How noble the course of this justly celebrated physician! After thoroughly investigating the theories of all his predecessors, and writing out a theory of his own, which, when he came to practice, he found so uncertain and dangerous, that he would not leave it, with his sanction, to entail misery and death on future generations. He therefore gave his dying advice to the world, with a full knowledge of the value of all the systems of medicine that had preceded him, to use a few simple medicines, and reject all physicians. Had this advice, given in the seventeenth century, been regarded by the world, what a vast amount of suffering and human life would have been saved! Its benefits would have been incalculable. A monument should have been erected to his memory, on which should have been inscribed in letters of gold,

"Here Lies An Honest Man, The Noblest Work Of God."

Succeeding Boerhaave, were Haller, Cullen, Hunter, Bostock, Brown, Rush, and Chapman, of modern times; the history of whom may be told in the language of Thomas Jefferson, the illustrious statesman and philosopher. In a letter to Dr. Wistar, he says, "I have lived myself to see the disciples of Hoffman, Boerhaave, Cullen, and Brown succeed one another like the shifting figures of the magic lantern; and their fancies, like the dressers of the annual doll babies from Paris, becoming from the novelty the vogue of the day, each yielding to the next novelty its ephemeral favors. The patient, treated on the fashionable theory, sometimes gets well, in spite of the medicine; the medicine therefore cured him, and the doctor receives new courage to proceed in his bold experiments on the lives of his fellow-creatures. "I believe," continues Mr. Jefferson, "we may safely affirm, that the presumptuous band of medical tyros, let loose upon the world, destroy more human life in one year, than all the Robin Hoods,

Cartouches, and Macbeths do in a century. It is in this part of medicine I wish to see a reform, an abandonment of hypothesis for sober facts, the highest degree of value set upon clinical observation, the least on visionary theories."

Dr. William Brown, who studied under the famous Dr. William Cullen, lived in his family, and lectured on his system, says in the preface to his own works, "The author of this work has spent more than twenty years in learning, teaching and scrutinizing every part of medicine. The first five years passed away in hearing others, and studying what I had heard, implicitly believing it, and entering upon the possession as a rich inheritance. The next five, I was employed in explaining and refining the several particulars, and bestowing on them a nicer polish. During the five succeeding years, nothing having prospered according to my satisfaction, I grew indifferent to the subject; and with many eminent men, and even the vulgar, began to deplore the healing art, as altogether uncertain and incomprehensible. All this time passed away without the acquisition of any advantage, and without that which, of all things, is most agreeable to the mind--the light of truth; and so great a portion of the short and perishable life of man was totally lost! Here I was, at this period, in the situation of a traveler is an unknown country, who, after losing every trace of his way, wanders in the shades of night."

Dr. Brown's experience probably differs in only one particular, from that of every student of the theories of medicine, and that is, he spent seventeen years longer than is customary, to obtain authority to kill according to law.

Dr. Rush says, in his lectures in the University of Pennsylvania, "I am insensibly led to make an apology for the instability of the theories and practices of physic. Those physicians generally become most eminent, who soonest emancipate themselves from the tyranny of the schools of physic. Our want of success is owing to the following causes,--1st, Our ignorance of disease, of which dissections daily convince us. 2, Our ignorance of a suitable remedy, having frequent occasion to blush at our prescriptions."

Had not Rush so soon fallen a victim to his own favorite practice of bleeding, he would unquestionably have laid a foundation for medical reformation, that would ere this have swept away those false theories with the besom of destruction. He says, "We have assisted in multiplying diseases; we have done more--we have increased their mortality. I will beg pardon of the faculty for acknowledging, in this public manner, the weakness of their profession." He then speaks forth in the dignity of his manhood, and from the honesty of his heart, "I am pursuing truth, and am indifferent where I am led, if she only is my leader." A man of so much benevolence and conscientiousness as the venerable Rush could not long have reconciled his acknowledgments and practice.

Dr. L. M. Whiting, in a dissertation at an annual commencement in Pittsfield, Mass., frankly acknowledges that "the very principles upon which most of the theories involving medical questions have been based, were never established. They are, and always were, false; consequently the superstructures built upon them, were as the baseless fabric of a vision, transient in their existence; passing away before the introduction of new doctrines and hypotheses, like dew before the morning sun. System after system has arisen, flourished, and been forgotten, in rapid and melancholy succession, until the whole field is strewed with the disjointed materials in perfect chaos; and amongst the rubbish, the philosophic mind may search for ages, without being able to glean from hardly one solitary well-established fact."

Dr. Benjamin Waterhouse, after lecturing in Harvard University twenty years, retired, saying of all he had been so long and zealously teaching, "I am sick of learned quackery."

We have now clearly shown, by incontestable evidence, that the science of medicine, as taught in the schools of physic, is based on no established principles, and therefore must be false in theory, and destructive in practice. Can the object of medical science be accomplished by these theories, while all admit that object to be the prevention and cure of disease ?