MATERIA MEDICA. INTRODUCTORY OBSERVATIONS. THE SCIENCE OF MEDICINE has for its object the alleviation. and cure of disease. Two kinds of agents are employed, MORAL and PHYSICAL, the study and investigation of which constitute ACOLOGY, or the Science of Remedies. MORAL agents are employed to impress the mind and feelings, and are not to be overlooked by physicians; while physical agents are employed to act upon the body, and remove corporeal ailments. PHYSICAL agents are derived from the material world in which we dwell. Some of them are absolutely necessary for the maintenance of life, and by proper management can be made to play an important part in the treatment of diseases; they come under the head of Hygienic Remedies. Others consist of substances found abundantly in the three kingdoms of nature, the Animal, the Vegetable, and the Mineral, which have been proved by observation and experience to have a decided controlling or perturbating influence over the organs of the body. These constitute the MATERIA MEDICA. There are other agents which are mechanical in their application, but which so influence vital movements as to be important in diseased states; as venesection, issues, setons, acupuncture, &c. A knowledge of the power and the application of remedies is the foundation of Therapeutics. The term PHARMACOLOGY is employed for that of Materia Medica. It is more comprehensive. The articles of the Ma teria Medica, whether simple or modified, are called Medicines. PHARMACY is the art of preparing them for use; and by THERAPEUTICS is meant the application, guided by principles, which is made of them in the treatment of disease. PHARMACOLOGY embraces all of these subjects. Medicines may be defined to be substances, derived from the organic and inorganic kingdoms, which inherently possess the power of affecting the solids and fluids of the body, and, through them, so changing the functional and organic movements as to be serviceable in diseased conditions. Some articles of Diet will be found in the list of the Materia Medica, which have been there placed for convenience, in consequence of their adaptation to diseased states of the organs. A distinction is to be drawn between an article of food and a medicine; it depends essentially upon the assimilative capabilities of the former;-exceptions. A distinction is also to be drawn between a medicine and a poison. This is more difficult, as medicines may become poisons, or poisons may be used as medicines. It is the application which determines whether articles of the materia medica are to be regarded as one or the other. When the impression is inordinate, so as to become injurious to the organs, the article used may be said to be poisonous. The dose, peculiarities of constitution, and pathological conditions, influence the effects. Inordinate medication is poisonous medication. As there is some relation between food and medicines, so is there between food and poisons. Instances cited where food has acted poisonously. The study of medicines involves attention to a number of circumstances, which may be divided into such as pertain to them as simple bodies, such as are important in a pharmaceutical point of view, and such as belong to them as therapeutic means. Crude medicinal articles are obtained, by commerce, in the form of drugs, and, as such, must be studied with respect to their sources or localities of production, their natural history, the modes of collecting and preparing them for the market, and their sensible properties. INTRODUCTORY OBSERVATIONS. 11 As objects of Pharmacy, their chemical composition and relations must be investigated. With reference to Therapeutics, their modes of operating, doses, appropriate application, and toxicological effects must be inquired into. Importance of knowing the localities from which drugs are derived. The study of Botany and Natural History recommended. Medicines are the tools of the profession; a knowledge of their sensible properties shown to be of absolute necessity. A familiarity, of a practical character, with medicines cannot be dispensed with without entailing embarrassment and difficulty. In this connection, the subject of adulteration alluded to, and means of detecting it pointed out in general. The distinction between indigenous and exotic productions, and definitions. That mode of growth, including soil, climate, and tillage, is a powerful modifier of the properties of vegetables exhibited by examples; and the modes of collection and preparation shown to affect their virtues. This subject is connected with vegetable physiology. The importance of Chemistry exhibited in determining the composition of articles and separating their Principles. These are divided into Organic or Proximate, as distinguished from Elementary. Illustrations.-Chemistry is essential to the operations of pharmacy, and in compounding medicines. It also affords the antidotes to poisons. But it is further important, in determining the changes which medicines undergo in the economy, and the alterations which are made in the solids and fluids, as therapeutics is connected with such modifications. Some recommendations given as to the course of reading to be pursued, and the books best calculated to aid the student. A Pharmacopoeia defined; its objects, importance, and advantages stated. The propriety of adhering to the national authority, the United States Pharmacopoeia, insisted upon. Nomenclature, and its importance explained. EFFECTS OF MEDICINES. These cannot be determined except by observation and experiment, although various methods of determining them à priori have been devised. Speculation upon the effects of medicines has answered no good purpose; and we are forced to have recourse to experiment. When their effects have been determined, classification is admissible. Allusions made to natural history and other relations. Medicines act by modifying the solids or fluids: upon the former by augmenting or diminishing their vital movements; and upon the latter by increasing or lessening their quantity, or altering their qualities. In these ways alone, the functions of organs, as well as the interior vital operations, termed organic, which are involved in assimilation or nutrition, are impressed and modified. It is not meant, however, that they are directed to one or the other exclusively. Both are intimately connected in disease. Effects are exhibited by phenomena, which are apparent sooner or later. Some of them are rapid, while others are tardy in their appearance. Proof of this presented. The effects are divided into primary and secondary. The first are also called physiological, because they equally occur in health. The secondary effects are induced through the primary; they are remote, and through them disease is removed or relieved; they are dependent on pathological as well as physiological laws; and, as they afford the therapeutical plan of action, are called sometimes the therapeutical effects. The explanation of the effects and of the mode of their production, so far as possible, is known as the modus operandi. Illustrations of the primary and secondary effects given, derived from those of a purgative, a diuretic, or a sudorific, and an explanation given of what is meant by an indication, and the means of fulfilling it. The primary and secondary effects are not always distinct: the primary becomes, in some cases, the therapeutical, as in the |