Macclesfield Borough
Maidstone BoroughMerionethshire Constab'
Mersey River Police
Mersey Tunnels Police
Manchester AirportMerseyside PoliceMinistry of Defence
Manchester City PoliceMerthyr Tydfil BoroughMinistry of Munitions
Manchester Docks
Monmouthshire Con'
Metropolitan Dockyard
Metropolitan Police
Manchester Sheff' Lincs
Manchester Ship Canal
Margate Borough PoliceMotherwell & Wishaw
Middlesbrough Borough
Midland Counties Rail'
Midland Railway Police