ABSTRACT
After Alessandro Volta (1800) presented the so-called Volta cell, practicable applications were wanted. First example of use of the Volta cell was the electrical telegraph invented by Sömmering in 1810. Here the voltage of the Volta cell was served for the transmission of letters of the alphabet through a four-line cable from one place to another. The hydrogen development observed on the positive electrode limited extremely the application. So scientists tried to eliminate the polarization originated by hydrogen with chemicals, e.g. with oxidizing agents.
