Imperial and US customary measurement systems (42 US gallons, 34.97 imperial gallons or 159.0 litres) used in the oil industry has the dimension of volume and could be replaced by the gallon, cubic metre or litre. The definitions of potential difference (volt), electric current (ampere), electrical resistance (ohm) were defined in terms of metric units, international agreement having been reached at a series of IEC Congress in Chicago between 1881 and 1906 when the electrical industry was in its infancy. At that time the metric system had become established in continental Europe while in the United Kingdom metrication was an active issue. Similarly, the units of
The Civil Wars: A Tree Is Best Measured When It Is Down The Civil Wars: A Tree Is Best Measured When It Is Down the CIVIL warS: a tree is best measured when it is down is an opera created in the early 1980s by director Robert Wilson to music by Philip Glass, David Byrne, Gavin Bryars and others. The vast five-act work has never been performed whole. Originally, "The Civil Wars" was conceived as a single daylong piece of music theatre to accompany the 1984 Summer Olympics. Six different composers from six different countries were to compose sections of Wilson's text inspired by the American Civil War. After initial premieres in