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T H E JOURATAL O F I S D U S T R I A L A N D EiVGINEERING C H E M I S T R Y .
June,
1912
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EDITORIALS THE SCOPE OF PHARMACEUTICAL CHEMISTRY.
The term Pharmaceutical Chemistry conveys no very definite idea t o many who are engaged in other branches of the science; and with these indeed, may be included many who are connected with this branch of chem$try. For this condition, the pharmaceutical chemists themselves are responsible. Men engaged in the various divisions of pharmaceutical work, forgetting how dependent they are upon the other classes of workers in this field, have failed t o keep in touch with one another. With this condition existing among the pharmaceutical chemists it is not difficult t o understand why other chemists often have vague ideas as t o what pharmaceutical chemistry comprises. The term should be applied to the chemistry directly involved in the preparation and dispensing of medicines, in other words, t h a t connected with the practice of pharmacy in any of its branches. The retail pharmacist often makes chemical and microscopical examinations of urine, or even maintains a general commercial laboratory; and the chemist in a manufacturing house may be called upon to examine flue gases, coal, paints and other materials used in construction work, b u t none of these can be included in the branch of chemistry under consideration, There are four well defined divisions of pharmacy in which chemistry plays a n important part-Retail Drug Business, Pharmaceutical Education, Pharmaceutical Manufacturing, and Drug Inspection. These divisions originated in the order named and each is directly dependent upon those preceding it. The retail drug store is the unit upon which the whole structure of pharmacy rests and from which the ot.her divisions were evolved. A considerable knowledge of chemistry is required by the successful prescriptionist to whom many difficult problems come. The retail pharmacist also manufactures a certain number of his preparations, and his manufacturing operations should differ only in magnitude from those of the manufacturing pharmacist which we shall consider later. The retail pharmacist should also be competent t o inspect his purchases of drugs and chemicals and this requires careful analytical work. Hence, the purchase of a medicine a t the drug store or the compounding of a prescription should not be considered as a commercial transaction, b u t as a professional service and should be paid for accordingly. While conditions in pharmacy are not ideal, rapid advancement is being made and the attitude of the public toward the pharmacist, influencing as i t does the financial returns of t h e business, will be an important factor in pharmaceutical progress. In the early days of scientific pharmacy the education of the apprentice was an important duty of the proprietor, but as pharmacy developed, schools were organized for the purpose of training men to act as retail pharmacists. Further progress, however, brought a demand for men trained to fill positions as
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chemists for manufacturing houses, boards of pharmacy, drug commissioners, etc. The schools have not met this demand and in most cases men must be selected who have a pharmaceutical education with very little chemical training or a good training in chemistry and no knowledge a t all of pharmacy. The knowledge of chemistry or pharmacy which is lacking must then be obtained and, as the latter is more easily acquired, such positions are usually filled by men who have little or no knowledge of pharmacy. This condition is very unsatisfactory as the chemist may be handicapped for years b y his ignorance of pharmaceutical conditions and facts which have never happened to come to his attention. I t is true t h a t attempts have been made by some of the colleges, t o provide courses for chemists who wish to take up pharmaceutical work, b u t most of them have failed t o provide training of the proper sort. Four-year pharmacy courses are often built up by taking a two-year course as a basis and attaching here and there a more or less unrelated subject until the time ,is reasonably well filled. Another idea is t o devote a third year, after the regular two-year pharmacy course, t o food and drug analysis. Bacteriology, botany, mineralogy, toxicology, urine analysis, water analysis, fire assaying and other interesting subjects are available for the construction of such courses; and there seems t o be little realization of the fact t h a t four years is a very short time in which t o train men for pharmaceutical work, even if the curriculum is well chosen. The ideal training would include a knowledge of the retail drug business although this is not absolutely essential ; the essential features are instruction in pharmacy and as broad a training in chemistry as possible. Of course, i t is understood t h a t mathematics, physics, languages and other subjects must be included in a course of this kind. Graduate courses of study should be established so t h a t pharmaceutical chemists could pursue their studies under competent instructors. We believe t h a t t h e cause of this unsatisfactory condition in pharmaceutical education is found in the fact, already noted, t h a t the men in any one of the divisions of pharmaceutical work have not sufficiently interested themselves in the work of the other divisions ; and thus the educational men have had little opportunity to learn what is required in the other lines of work, The chemical work of the manufacturing pharmacist is varied in character; and in order t o gain a clearer idea of its nature i t may be well to consider it in several steps. The inspection of crude materials is obviously a most important factor in the production of a good product. This inspection consists in the positive identification of everything purchased, exclusive of those things which are identified by a botanical examination; and as thorough a study as possible of the purity and strength of the material. Drugs of vegetable or animal origin containing known active principles must be assayed in order to deter-
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mine their value The determination of the naturc and amount of impurities in organic and inorganic chemicals, oils, resins, gums, balsams, etc., taxes the resources of any chemist, and the pharmaceutical chemist is often driven t o the expedient of rejecting clearly unsatisfactory materials on account of the presence of unidentified impurities. In choosing materials it is understood t h a t certain amounts of harmless impurities must be permitted in all medicinal substances otherwise their cost would be prohibitive. Having determined t h a t the crude materials are satisfactory, the manufacturing processes must be controlled b y the examination of preparations in different stages of manufacture in order t o give directions for finishing products of proper strength and composition. The finished products must then be examined t o determine their compliance with standards of strength and purity, and also b y aging experiments t o determine something of their keeping qualities. It is said t h a t it is impossible t o remain stationary; if this is true no manufacturer can stop when he has accomplished what has been outlined above; he must strive t o advance. Many of the analytical methods used in this work leave much t o be desired and a constant effort must be made t o improve them. Manufacturing processes must be improved in order t o produce better products and, t o make them more economically, new processes and new products must also be devised. With the enactment of food and drug laws the inspection of drug products became a very important division of pharmaceutical work. Extremely valuable results have already been achieved by workers in this field and b y conservative work much more will be accomplished. The sensational methods and arbitrary rulings which have, in a few instances, been resorted to, are, however, t o be greatly deplored. Having discussed our subject in a general way i t may be of interest t o give some definite idea of the number of substances with which the pharmaceutical chemist has t o deal. A certain manufacturing house lists about four thousand products, in the preparation of which about seven hundred different materials, which must be examined chemically, are used. Pharmaceutical chemistry presents an inviting field of work t o the young chemist. Comparatively little is known concerningthecomposition of many of the hundreds of vegetable drugs in use. Even in case of some of the most important drugs our knowledge is
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very defective Ergot may be cited as an example, the most important contributions to our knowledge of its composition having been made within the last few years, although its study has been undertaken b y many eminent chemists during a period extending over many years. The composition of the vegetable drugs alone offers an interesting and impnrtant field of work for the pharmaceutical chemist for generations t o come. The effect of cultivation upon t h e chemical composition of medicinal plants has been almost entirely neglected, although the remarkable increase in the quinine content of cinchona bark through cultivation has long been known. The relation of chemical constitution t o physiological action, and the study of the enzymes and hormones which may be used medicinally are merely suggestive of the broad fields which await the pharmaceutical chemist of the future. While a review of the progress of pharmacy would not be appropriate here it may not be out of place t o call attention to the several lines of cooperative analytical work which are being carried on. The keeping quality of medicinal preparations has already been referred to and this subject has had the serious consideration of manufacturers for a number of years. Several of the largest manufacturers have collaborated on this work and have published the results already obtained in the form of a brochure on the "Stability of the Drug Extracts " The work has shown t h a t preparations of this class are as a rule remarkably stable. The pharmaceutical division of this society has a Committee on Quantitative Methods whose function is the study and improvement of analytical methods used in pharmaceutical work. The U. S. Pharmacopoeia and the National Formulary, which are our official standards for medicinal substances, are now being revised, and in these great undertakings a large number of workers in all branches of pharmacy are collaborating. As these works do not include all articles which are commonly used in medicine, the American Pharmaceutical Association has a standing committee for the establishment of unofficial standards in which all classes of pharmaceutical workers are represented. As the pharmaceutical chemists are thus striving to advance this branch of chemistry, it is t o be hoped t h a t they will not neglect any opportunity for furthering closer relations with one another and with chemists in other lines of work. F. R. E L D R E D .
ORIGINAL PAPERS STRUCTURE OF GALVANIZED IRON. BY
W A L T E R ARTHUR AND W I L L I A M
H
XI'ALKER
Received December 11, 191 1
Galvanized iron, by which term in this article we shall include all zinc protected iron, consists not of a sheet of iron covered with a layer or skin of pure zinc,
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as one might expect, but, on the contrary, of a complicated system of iron-zinc compounds, starting with pure zinc on the outside and passing through these alloys t o the iron base within. We shall consider the structure of zinc protected iron under the three heads: I . Hot galvanized-material made by passing the iron through a bath of melted zinc
