The American new dispensatory : containing general principles of pharmaceutic chemistry ; pharmaceutic operations ; chemical analysis of the articles of materia medica ; materia medica, including several new and valuable articles, the production of the United States ; preparations and compositions ; with an appendix, containing medical prescriptions ; the nature and medical uses of the gases ; medical electricity ; galvanism ; an abridgment of Dr. Currie's reports on the use of water ; the cultivation of the poppy plant, and the method of preparing opium ; and several useful tables ; the whole compiled from the most approved authors, both European and American / by James Thacher.

  • Thacher, James, 1754-1844.
Date:
1810
Catalogue details

Licence: Public Domain Mark

Credit: The American new dispensatory : containing general principles of pharmaceutic chemistry ; pharmaceutic operations ; chemical analysis of the articles of materia medica ; materia medica, including several new and valuable articles, the production of the United States ; preparations and compositions ; with an appendix, containing medical prescriptions ; the nature and medical uses of the gases ; medical electricity ; galvanism ; an abridgment of Dr. Currie's reports on the use of water ; the cultivation of the poppy plant, and the method of preparing opium ; and several useful tables ; the whole compiled from the most approved authors, both European and American / by James Thacher. Source: Wellcome Collection.

Provider: This material has been provided by the National Library of Medicine (U.S.), through the Medical Heritage Library. The original may be consulted at the National Library of Medicine (U.S.)

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    of gums or saline substances in water. But in these the marks of chemical combination are still present, the compound is homo- geneous, and cannot be decomposed but by the exertion ot a su- perior affinity. Chemical attraction is not invariably or equally exerted by each substance to every other. Between many substances there- seems to exist no attraction, at least they cannot be made to combine together. Others ht\ve a very extensive power of com- bination, and seem capable of uniting with almost every sub- stance which is not already saturated with them; and there are many intermediate, in their facility of combination, between these two extremes. Chemical attraction is not limited, in its action, to two bodies. It can be exerted between three, four, or more, and can thus form compounds of so many principles. It can likewise unite bodies in different proportions. Some combine in every pro- portion, others only in limited quantities. In the latter case, the compounds formed by the different proportions have in general very different properties. The compounds which are thus formed, have still the same relation to chemical attraction. They have a tendency to com- bine with other bodies, simple or compound; they can combine in various numbers and proportion; and these combinations are accompanied by the same phenomena, and regulated by the same laws. The attraction exerted by any substance towards others, is not uniform in its force. To some it is stronger, to others weaker. Hence it follows, that if two bodies have been com- bined together, they may be separated, or the compound they have formed may be destroyed, by presenting to it another sub- stance, which exerts an attraction to one of its component parts, superior to the attraction by which they were held united. If the circumstances necessary to favour the exertion of chemical attraction be present, the two bodies between which there is the strongest attraction combine, and the other is separated. In chemical language this process is termed decomposition, from a single elective attraction. A case of decomposition, more complicated, is that, where two compounds are mixed together, and where the constituent parts of the one exert attractions to those of the other stronger than the attractions by which they are held combined m the original compounds. In this case, a complete exchange takes place, and two new compounds are formed. This is termed double decom- position, or the exertion of a double elective attraction. Tables have been constructed of the relative forces of attractions of many bodies towards others, whence may be estimated the combina- tions or decompositions that will take place on their mixture with each other. The exertion of chemical attraction between bodies is greatly influenced by another power, that of heat or caloric. This is the cause of the temperature of bodies, of their expansion, fluidity, and conversion into the aeriform or gaseous state. Its