We all use watches. The creation of modern devices has greatly facilitated human life. Before, time was also necessary to watch, so there were other watches. And they called them an interesting word "gnomon." From ancient Greek it is translated as a "pointer". What were they like, how were they used before? We will talk about this today.
Gnomon - the most accurate indicator of true time
Gnomon is an ancient astronomical tool that allows you to determine the angular height of the sun by the smallest length of the shadow of its column. Such peculiar watches were created a long time ago, they helped to determine the time on a sunny day. The sun here just plays a key role, more precisely, the shadow of it. In other words, the gnomon is the simplest sundial.
In addition to the column and the shadow from it, the watch has a dial, which allows you to more accurately determine the time and, accordingly, the height of the sun.
At different points on the earth, the division of the dial will not be the same. It depends on the specific point where the gnomon is supposed to be installed. In astronomy, such a device is designed to determine the height of the sun. During the day it is located at different points, respectively, the shadow cast by objects also varies. This allows you to know the time. The determination is made by degrees of the arc. The azimuth and height of the sun - that is what allows you to determine it accurately. In addition, for example, the day of the equinox is found out from the shadow of the gnomon, for example, with any date. These watches may look different. More often than not, this is a circle on a plane with a triangle attached to it. It is easy to determine the time by the sundial, but how accurate is it?
How are sundials different from ordinary ones?
The sundial is always either in a hurry, or somewhat behind the present. Only four times a year do they show the absolutely correct time, but on other days they do not coincide with it. In fact, a sundial shows the correct time, and not a wristwatch invented by people. But nevertheless, in order to better orient themselves in time, they use a special schedule, which, as a rule, is placed next to the clock. Usually, there are two ways to know the time in a sundial.
Shadow of the Gnomon - a pointer to time
A clock is called a Gnomon, but to be more precise, this is just a part of them, namely, an object casting a shadow. Most often it is a triangle. The angle of inclination depends on geographical latitude. Gnomon is always directed north. An exact watch has two gnomons. One face is a curved outline.
It was made with the aim of not confusing which of the faces to measure time, but it looks quite aesthetically pleasing. Also for aesthetics, you can make the gnomon slightly curved. The most important thing is that the face intended for recording time is straight.
Variety of Sundials
Sometimes a watch is created that has three gnomons at once. The first gnomon is the one that measures the local time, the second measures the time zone, and the third is needed to measure the azimuth of the sun.
Interesting about sundial
A sundial, unlike a wristwatch, shows real solar time, while the time invented by man is greatly simplified. In the sundial you can clearly see noon. The interval between two noon is called a sunny day. A sundial directly depends on the sun, and it is almost impossible to construct a mechanical assembly oriented to the sun. The time invented by man is not only not exact, but also constant, which excludes this very accuracy.
Thus, the gnomon is one of the main parts of a sundial. It looks like a beautiful design. Observing the gnomon allows you to find out the exact time, depending on the sun, that is, true.