A manual of magnetism : including galvanism, magnetism, electro-magnetism, electro-dynamics, magneto-electricity, and thermo-electricity.

  • Davis, Daniel.
Date:
1847
Catalogue details

Licence: Public Domain Mark

Credit: A manual of magnetism : including galvanism, magnetism, electro-magnetism, electro-dynamics, magneto-electricity, and thermo-electricity. 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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    was supposed to pass through the liquid between the plates ill a direction from the zinc to the copper or platinum. This passage of electricity through fluids which are not themselves elementary, is attended always, according to Faraday, with decomposition, whether the fluid is between the plates of the bat- tery or interposed in the course of the wires or poles leading from it. Thus, where a battery is excited simply by water, that fluid is decomposed; its oxy- gen attacks the zinc, and its hydrogen is given off in contact with the electro-negative metal. 27. In Smee's battery, the water of the acid solution may also be considered as undergoing de- composition, one atom of its oxygen uniting with one atom of zinc, in order to enable the sulphuric acid to unite with the resulting oxide of zinc, and the corresponding atom of hydrogen being given off in contact with the platinum. It will be observed that the oxygen and hydrogen appear at the opposite sides of the fluid undergoing decomposition. It is not, however, believed that these elements travel through the intervening distance, but that the two atoms of water in contact with the plates are simul- taneously decomposed, and that a chemical equilib- rium is then established by a progressive exchange of elements in all the intervening particles. The sub- ject of electro-decomposition will be further spoken of in connection with the electrotype. 28. The gas which is so plentifully disengaged at the surface of the platinum in this battery is apt to bring the strip into contact with the zinc, and thus