[3] The use of coal gas for illumination and heating had expanded since its invention in the early 18th century by William Murdoch, a Scottish engineer.

By the middle of the nineteenth century there were nearly one thousand gas companies within Great Britain with thirteen in London.

The Act included the first attempt to produce a standard measure for energy supply when it defined the term candle power.

The monopoly status of the gas companies led to overcharging and abuse resulting in a public outcry.

A select committee was formed to decide on the best response, and as a result the City of London Gas Act 1868 (quickly extended to cover the entire metropolitan area) tried to regularise this by forcing the remaining gas companies to open their accounts to public view.