Watt within the then-existing system of practical units as "the power conveyed by a current of an Ampère through the difference of potential of a Volt." In October 1908, at the International Conference on Electric Units and Standards in London, so-called "international" definitions were established for practical electrical units. Siemens' definition was adopted as the "international" watt. (Also used: 1 ampere x 1 ohm.) The watt was defined as equal to 10 units of power in the "practical system" of units. The "international units" were dominant from 1909 until 1948. After the 9th General Conference on Weights and Measures in 1948,
Ohm and the CGS unit. Although called "legal", this standard was not adopted by any national legislation. The "international" ohm was recommended by unanimous resolution at the International Electrical Congress 1893 in Chicago. The unit was based upon the ohm equal to 10 units of resistance of the C.G.S. system of electromagnetic units. The International Ohm is represented by the resistance offered to an unvarying electric current in a mercury column of constant cross-sectional area 106.3 cm long of mass 14.4521 grams and 0 °C This definition became the basis for the legal definition of the ohm in several countries. In