Edward Weston (chemist) instruments for electric current—the modern foundation for the voltmeter, ammeter and wattmeter. In 1888 he formed the Weston Electrical Instrument Corporation which would become famous for its voltmeters, ammeters, wattmeters, ohmmeters, frequency meters, transformers, and transducers. Weston developed a method for producing a "true" permanent magnet. Weston conceived of and built a magnetic speedometer. Weston also developed the dashboard ammeter for Harley-Davidson motorcycles. Also in 1888, Weston became president of the American Institute of Electrical Engineers (AIEE) until 1889. Weston invented and patented the saturated cadmium cell in 1893. The cathode in the cell is an amalgam of cadmium with
Coal measures Coal measures The coal measures is a lithostratigraphical term for the coal-bearing part of the Upper Carboniferous System. The Coal Measures Group consists of the Upper Coal Measures Formation, the Middle Coal Measures Formation and the Lower Coal Measures Formation. The group records the deposition of fluvio-deltaic sediments which consists mainly of clastic rocks (claystones, shales, siltstones, sandstones, conglomerates) interstratified with the beds of coal. In most places, the coal measures are underlain by coarser clastic sequences known as Millstone Grit, of Namurian age. The top of the coal measures may be marked by an unconformity, the overlying rocks being