Except the Lord keep the City, the wakeman waketh in vain. 

Until 1888, Ripon ran its own justice system, policing its streets fully independent of the rest of Yorkshire. The Ripon Wakemen would stay awake and patrol the surrounding area from dusk till dawn. He kept a watchful eye for any approaching enemy or troublemakers, while people slept safely in their beds. The Wakeman would blow the horn at the four corners of the market cross each evening at 9pm to let the people know that the watch was set and the Wakeman was now on patrol. Today, the Ripon Police Force is remembered every evening when the Wakeman, now Hornblower, ‘sets the night watch’ in the Market Place, in the same way, a tradition that has lasted for 1100 years. 

The quote above the Town Hall is based on Psalm 127 - Unless the Lord watches over the city, the watchman stays awake in vain.