Standard candles

Generally, the passage of time is not measured in most parts of the Sorendenese Empire, but in the larger towns and cities 'standard candles' are used to help coordinate services and commerce. A standard candle burns for approximately an hour.
Standard candles are actually rather small and in some places larger candles marked with hourly graduations on the side are used instead.
The temple of Mithra is responsible for coordinating the service with secular 'Candle Callers' being used to call the time through the streets.
The number of the candle being called is restarted at both dawn and dusk to tie in with the appropriate Mithran religious rites. No candle calling is done at either of these times because it would interfere with these ceremonies, but the first candle for the new period—be it day or night—is lit.
This means the first call after dusk is named the first candle of the night and it occurs about an hour after the sun sets.
This system is far from precise, but clockwork hasn't been invented yet and it does provide a means for people to coordinate in a city.