The chemical pocket-book, or memoranda chemica; arranged in a compendium of chemistry ... with Bergman's table of single elective attractions / as improved by Dr. G. Pearson.

  • Parkinson, James, 1755-1824
Date:
1807
Catalogue details

Licence: Public Domain Mark

Credit: The chemical pocket-book, or memoranda chemica; arranged in a compendium of chemistry ... with Bergman's table of single elective attractions / as improved by Dr. G. Pearson. Source: Wellcome Collection.

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    CHEMISTRY. CHEMISTRY is the Science which discovers the Constituent principles of bodies, the results of their various combina- tions, and the laws by which those combinations are effected. Chemical inquiries are prosecuted by certain operations or processes; which are performed either by Analysis, or De- composition, or by Synthesis, or Composition. These ope- rations depend on the affinities, or powers of attraction, which act on bodies, and on the elementary parts of bodies. The Attraction of Aggregation is that by which the homogeneous particles of bodies are united. The Attraction of Composition, called also Chemi- cal Attraction, is that by which the heterogeneous parti- cles of bodies are united. Its action is inversely as that of the attraction of aggregation, since its operation must necessarily be impeded by that force of aggregation which allows but few of the ultimate molecules to be exposed to its influence. The general principles, or laws by which this pow er acts, are, accord- ing to Fourcroy, the following: 1. It unites bodies of different natures. Thus acids com- bine with alkalies, alkalies with sulphur, metals with acids, &c. 2. It only takes place between the ultimate, molecules of bodies. Agreeable to this law, a state of extreme division is necessary in bodies thus acted upon. 3. The Attraction of Composition may take place between two or more, bodies. The possible number of combinations thus resulting from the various intermixture of fifty-seven inde- composable bodies, considered as being combined two and two,