“The St. Lawrence is mere water. The Missouri muddy water. The Thames is liquid history.” So declared John Burns – a great advocate of London’s history – when asked to compare the Thames against those other great rivers in 1929. Forty years earlier in 1889 Burns had been a towering figurehead of the Great Dock Strike, thus sealing his own place in those murky waters. As the 125th anniversary of the strike approaches (14 August – 16 September) it feels an opportune moment to reflect on what this particular passage of liquid history might mean today.