Clark, Latimer

Clark, Latimer. An Elementary Treatise on Electrical Measurement for the Use of Telegraph Inspectors and Operators. London E. and E. N. Spon, 1868. An interesting historical artifact that predates the identification of electrons and their role in electric current and measurement. 

The Clark cell was patented by Latimer Clark in the 1880s, and was the first standard cell. 

Clark cell A type of cell formerly used as a standard source of e.m.f. It consists of a mercury cathode coated with mercury sulfate, and a zinc anode. The electrolyte is zinc sulfate solution. The e.m.f. produced is 1.4345 volts at 15°C. The Clark cell has been superseded as a standard by the Weston (Trademark) cadmium cell. The cell is named for the English engineer Josiah Latimer Clark (1822-98). 

In 1861, at the urging of the telegraph engineers Sir Charles Bright and Mr. Latimer Clark, the British Association set up a committee to consider the need to establish a unit for electrical resistance and to decide the best form in which a standard could be kept. (39)... 

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