When the Jesuit Luís Fróis visited the Japanese lord Oda Nobunaga in 1569, he presented his host with a clock. Mechanical clocks were new to Japan, and this was a particularly exquisite example. Yet the feudal lord rejected the gift, saying “I do wish very much to have it. However, I do not want it because it would be wasted on me.”
What did Nobunaga mean? To start, the clock may simply not have made any sense to him. Oda Nobunaga was raised in a culture that told time in a different way: the hours he lived by were variable rather than fixed. In Japan’s traditional timekeeping system, the day was divided into nighttime and daytime portions, which were each subdivided into six intervals. In summer, the night hours grew shorter, and the daylight ones grew longer; in winter, the pattern reversed.
This system may sound odd to modern ears, but at one time it was quite common. Unequal hours were used throughout medieval Europe , and similar systems were in place in ancient Egypt, Greece, and Rome. A timekeeping system that reflected the portion of the day that was lit by the Sun made sense in an agrarian society with little access to artificial light.