What a cracking advert for the 'modern' force of electricity. The West Midlands Joint Electricity Authority was one of the very few post-WW1 'joint boards' set up and merged the generating capacity various borough electrical departments, including Shrewsbury, Cannock, Walsall, West Bromwich and Wolverhampton, with the privately owned Midlands Electricity Corporation to rationalise and improve generation and supply - the WMJEA built the 'super station' known as Ironbridge A adjacent to the Severn-side Ironbridge B station that still generates. The vignettes are very 'period' and remind me of the illustrations commissioned by the Southern Railway at the time for their electrification programme.