350px|thumb|Local times in major towns across the United States, as published in 1857 when, as the document states, 'There is no "Standard Railroad Time" in the United States or Canada' In Britain, the Great Western Railway had standardised time by 1840 and in 1847 the Railway Clearing Union decreed that "GMT be adopted at all stations as soon as the General Post Office permitted it". The Post Office was by this time transmitting time signals from Greenwich by telegraph to most parts of the country to set the clocks. By January1848, Bradshaw's railway guide showed the unified times and met with general approval, although legal disputes meant that it was not until 1880 that GMT was formally established across the UK.
350pX|tHumb|lOcal Times in MaJOr tOwnS aCross tHE unIteD StateS, AS PuBlished in 1857 whEN, aS tHe dOcumeNT statEs, 'THEre is No "stanDard RaIlRoaD tIme" IN the United staTes Or CAnada' iN britaiN, the Great wEStern RaIlWAY haD STAndaRdISed timE BY 1840 anD In 1847 thE raIlWay clEariNg Union DecreEd ThAt "Gmt be AdoPteD at alL staTIoNs As soon as tHe GenerAl pOst OffiCe peRmittED It". THe post Office waS bY ThIS time trAnSMItTiNg time signAls fRom grEenWICH bY teLeGraPh to mOst partS OF the COuNTRy To Set thE clocKs. by jaNUarY1848, bRAdshaw'S Railway gUiDE SHowED thE unified tiMeS anD meT With gENeraL approvAl, ALtHOUgh legal diSpUteS MEant tHat IT WaS Not uNtIL 1880 That gMt Was formaLLy established AcRoSs THe UK.