Voltaic battery

I formerly described a substance, sulphuret of silver, whose conducting power was increased by heat and I have since then met with another as strongly affected in the same way this is fluoride of lead. When a piece of that substance, which had been fused and cooled, was introduced into the circuit of a voltaic battery, it stopped the current. Being heated, it acquired conducting powers before it was visibly red-hot in daylight and even sparks could be taken against it whilst still solid. 

Grove, W.R. 1842. On a gaseous voltaic battery. Philosophical Magazine J Sci XXE417-420. 

The probability of manufacturing products by the electrolysis of fused salts was foreseen by M. Faraday 41 in 1834 before the development of the dynamo,-which replaced the voltaic battery as a source of electricity on a manufacturing scale. 

The capability of decomposing fused chlorides, iodides and other compounds and the opportunity of collecting certain of the products without any loss by the use of simple apparatus, render it probable that the voltaic battery may become a useful and even manufacturing instrument. 

It is in accordance with facts as I see them to compare the chemical action of light with that of a voltaic cell. Light separates the constituents of many ponderable compounds and forces them to form new compounds. . . just as the poles of a voltaic battery do to a still greater extent. 

Page 82. Potassium, the metallic basis of potash, was discovered by Sir Humphrey Davy in 1807, who succeeded in separating it from potash by means of a powerful voltaic battery. Its great affinity for oxygen causes it to decompose water with evolution of hydrogen, which takes fire with the heat produced. 

Using the voltaic battery, Davy showed that the alkaline earths, like the caustic alkalis, were compounds containing oxygen and previously unknown metals. His characterization and naming of the alkaline earth metals followed his discovery of them barium, strontium, calcium, and magnesium are the names he invented for these metals. Like the names sodium and potassium, they are still in use today. 

The voltaic battery provided Davy with a tool for analysis. Because it was a tool that seemingly could be made ever more powerful, Davy hoped that it might reveal the true or ultimate elements of bodies, not just the so-called el-... 

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