The first railway employees described as "police" can be traced back to 30 June 1826. A regulation of the Stockton and Darlington Railway refers to the police establishment of "One Superintendent, four officers and numerous gate-keepers". This is the first mention of railway police anywhere and was three years before the Metropolitan Police Act was passed. They were not, however, described as "constables" and the description may refer to men controlling the trains rather than enforcing the law. Specific reference to "constables" rather than mere "policemen" is made by the BTP website article "A History of Policing the Railway" which states "The London, Birmingham and Liverpool Railway Companion of 1838 reports 'Each Constable, besides being in the employ of the company, is sworn as a County Constable.'" Further reference is made by the BTP to "an Act of 1838...which according to J. R. Whitbread in "The Railway Policeman" was the first legislation to provide for any form of policing of the railway whilst under construction, i.e. to protect the public from the navvies more or less."