The Eclectic and general dispensatory : comprehending a system of pharmacy, materia medica, the formulae of the London, Edinburgh, and Dublin pharmacopoeias, prescriptions of many eminent physicians, and receipts for the most common empirical medicines / collated from the best authorities, by an American physician.

Date:
1827
Catalogue details

Licence: Public Domain Mark

Credit: The Eclectic and general dispensatory : comprehending a system of pharmacy, materia medica, the formulae of the London, Edinburgh, and Dublin pharmacopoeias, prescriptions of many eminent physicians, and receipts for the most common empirical medicines / collated from the best authorities, by an American physician. Source: Wellcome Collection.

Provider: This material has been provided by the Harvey Cushing/John Hay Whitney Medical Library at Yale University, through the Medical Heritage Library. The original may be consulted at the Harvey Cushing/John Hay Whitney Medical Library at Yale University.

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    metals soldered together in pairs, are placed transversely in the grooves of a well-season- ed wooden, or an earthenware trough, and nledin with a cement of resin and wax, to prevent any liquid from passing through ; after which, the diluted acid is poured be- tween the pairs, so that it touches the zinc of one pair, and the copper of another, aU ternately, the copper side of each double plate looking towards the same extremity of the trough throughout the arrangement, and the zinc side to the other extremity. This apparatus is named the galvanic bat- tery ; and the distances between the pairs of soldered plates should be from one-fourth to three.fourths of an inch each, according to the width of the trough. The intensity of action of this apparatus, as far as the production of heat is concerned, seems to depend on the size of the plates, or extent of their surfaces, but for producing chemi- cal decomposition, on the number of plates. The more improved apparatus now used, is a trough of earthenware.divided in its length by numerous partitions of the same mate- rial. Into each of the cells thus formed, and filled with the diluted acid, a plate of zinc and of copper are placed, but not so as to touch each other; and a communica- tion is made by a metallic arc between the zinc in one cell, and the copper in the next. As a chemical agent, galvanism is the most powerful of all the repulsive forces, and is capable of producing decompositions which could not otherwise be effected. By. its means the chemical constitution of the alkalies and the earths has been established, and their bases discovered to be substances hitherto unknown, which have been added to the list of metals. By placing a compound, one, for instance, of oxygen and an inflammable body, in con- nexion with the metallic wires proceeding from each end of a galvanic battery, the oxygen is attracted by the wire which is in Ahe positive state, and repelled by that which is negative ; while, at the same time, the inflammable is attracted by the nega- tive wire, and repelled by the other. Hence the components are separated, and obtain- ed in a distinct state. In the decomposi- tions thus effected, substances can be con- veyed to a distance, and even through in- terposed ponderable matter, by the galvanic influence ; a result which, however singu- lar, is well ascertained. Galvanism, like electricity, acts as a stim- ulus to the living system. Its effects on the animal body are a sensation of light to the eye; a sensation of acidity on the tongue, of pain on the muscles, and the excitement of strong muscular action. It would be entering too much into hypo- thetical discussion to attempt an explana- tion of the phenomena of galvanism ; par- ticularly as philosophers are not agreed upon the subject. Galvanism has not yet been employed as a pharmaceutical agent, except for detecting the presence of oxy- muriate, bichloride of mercury when exhibit- ed as a poison. (See Pakt 3.) On the forces of attraction and of repulsion every chemical, and consequently every pharmaceutical effect, more or less depends. A knowledge, therefore, of the laws which regulate these powers, is of the greatest importance, and forms the basis of all chem- ical science. Section II.* Every substance, whether it be regarded generally as forming a part of the mass of this globe, or particularly as an object of science, may be arranged in one or other of the three following classes; Solids, Fluids, and Gaseous Bodies. We shall now examine each of these classes separately, and endea- vour to describe the constitutions and com- binations of the substances composing them, which are objects of pharmacy. I. SOLIDS. Solid bodies are masses of homogeneous particles combined and held together by the attraction of aggregation or cohesion. The arrangement of the particles with re- gard to each other is often such as to pro- duce regular figures, in which case the solids are said to be crystallized. Cohesion and crystallization have been already consider- ed. A. CONSTITUTIONS OF SOLIDS. Arrangement of the principal Solids accord- ing to their Composition. I. Simple, or Undecompounded. Sulphur. Carbon. Metals. Phosphorus, Boron. II. Compounds. Oxides of Sulphur. Phosphorus. Charcoal. Metallic Oxides. ' -with Alkaliet. Sulphur ets of Metals. fixed Alkalies. Earths. Phosphurets of Carbon. Metals. * In drawing up this section, I have borrowed very freely from the third book of Thomson's System of Chemistry.