## Table of contents:

For centuries, mankind has used the sixgesimal system for measuring time. In this system, familiar to everyone today, every day is divided into 24 hours, every hour - into 60 minutes, and every minute - into 60 seconds. Why is this exactly the case? Is this done by people out of habit, or is there some kind of reinforced concrete inherent advantage in measuring time in this way?

## Who invented the hour

The ancient Greeks were the first to introduce the very concept of an hour. Before that, there were Ora - the goddesses of the seasons. They were in charge of the natural order of things in nature, subdividing themselves into certain time periods. The number of Op varied depending on which source of information was used. The most common number was three. In the period of late antiquity, this number reached twelve. It was from there that the idea of dividing day and night into twelve hours each period came from.

The division of each hour into 60 minutes and minutes into 60 seconds came from Ancient Babylon. The Babylonians used the sexagesimal number system in sciences such as mathematics and astronomy. They also divided the day into 360 parts, because that was their estimated number of days in a year. From there came the division of the circle by 360 degrees.

The system of twelve-hour day and twelve-hour night was also used in Ancient Egypt. The Egyptians did this, perhaps because there are twelve lunar cycles in a year. It is also likely that it was easier to count them that way, with the 12 knuckles on each hand. In any case, these systems were subsequently adopted all over the world and are now the standard for measuring time. But what if someone tries to change the accepted standards?

## Decimal time

In 1754, the French mathematician Jean le Rond d'Alembert proposed dividing all units of time by ten. He said: “It would be preferable that all divisions, for example livre, sous, tuise, day, hour, and the like, were divided into tens. Such a division would lead to much simpler and more convenient calculations, and it would be more desirable than an arbitrary division of the livre into twenty sous, sous by twelve deniers, days by twenty-four hours, hours by sixty minutes, and so on."

In 1788, French lawyer Claude Boniface Collignon proposed dividing the day into 10 hours, every hour by 100 minutes, every minute by 1000 seconds, and every second by 1000 levels. He also proposed a week of 10 days and dividing the year into 10 "solar months".

Slightly modifying this proposal, the French parliament ruled that the period "from midnight to midnight is divided into ten parts, each into ten others, and so on up to the smallest measurable part of the duration."

The system officially entered into force on November 24, 1793. Midnight started at zero o'clock (or 10 o'clock), and noon came at 5 o'clock. Thus, each metric hour turned into 2, 4 conventional hours. Each metric minute became equivalent to 1.44 conventional minutes, and each metric second became 0.864 conventional seconds. Calculations have become easier. Time could be written down fractionally, for example, 6 hours 42 minutes turned into 6, 42 hours, and both values meant the same thing.

To help people move to a new time format, watchmakers began producing watches with dials showing both decimal and old time. But people have not moved to the new time. In contrast, decimal time proved to be so unpopular that it was canceled 17 months after its introduction.

The decimal time was intended not only to make its calculation more convenient.All this was part of a revolution in the general system of payments. The system also gave rise to the republican calendar. In it, in addition to dividing the day by 20 hours, there was a division of the month into three decades of ten days. As a result, there were five days short of the year. They were placed at the end of each year. This calendar was also canceled at the end of 1805. The project was buried before it could take place.

## There are still fans of decimal time

After the innovation over time suffered a fiasco, it seemed that no one else would ever talk about such a thing. At least the French for sure. But it was not so. In the 1890s, Joseph Charles François de Rey-Paillade, president of the Toulouse Geographical Society, again proposed using the decimal system. He divided the day into 100 parts, which he called cés. Each was equal to 14.4 standard minutes. Minutes were divided into 10 decicés, 100 centicés, and so on.

Unfortunately, the Toulouse Chamber of Commerce passed a resolution in support of this proposal. Outside its borders, fortunately, common sense prevailed, and this proposal did not receive adequate support.

Finally, a final attempt was made in 1897 by the French scientific committee Bureau des Longitude. The secretary of this society was the mathematician Henri Poincaré. He made some compromise by keeping the 24-hour day. Poincaré divided the hour into 100 decimal minutes each. The minutes have been divided by 100 seconds. This project was also not approved. In 1900, the decision was made to abandon decimal time forever. Since then, no one dared to touch the clock again.