Candle clock hi-res stock photography and images - Alamy
Before the invention of clocks, "candle clocks" were used. They would burn for set amount of hours. If one wanted an alarm, you would stick a nail into the desired time length
Candle clock hi-res stock photography and images - Alamy
THE SURPRISING ROLE OF CANDLES IN TIMEKEEPING BEFORE MECHANICAL CLOCK - Rockridgecandles
An example of a medieval candle clock. People would hear the nail hit the ground, letting them know a certain amount of time had passed. These were used mainly by the rich,
Candle clock, Austria free public domain image | Look and Learn
Clock Candle and Old Keys Photograph by Ann Garrett - Fine Art America
Working of Candle Clock | Medieval candle, Candles, Summer theme