The hourglass is the keeper of time on our planet! This is one of the oldest watch movements. It was invented and brought into reality even before our chronology began. But no one will ever be able to find out who that brilliant man was who represented the passage of all time in the form of an hourglass. History does not know for certain who was able to clothe such an uncontrollable concept in a glass flask filled with quartz crystals.

The entry of watches into history

Europe in the Middle Ages actively used this ingenious device to determine its time. It is known that medieval European monks could not imagine their life without watches. Sailors also needed to understand the passage of time.

An hourglass was often used, which only kept time for half an hour. The duration of pouring sand from the top of the flask to the bottom could be about an hour. Despite its accuracy (and this is what the watch was famous for), such an invention in the future ceased to be popular among people. Although the inventors tried very hard and, in their attempts to improve the hourglass, even went so far as to be able to provide society with a huge glass flask capable of keeping time - 12 hours.

How does sand time work?

To obtain more accurate time data, only the most transparent glass was used in the production of this device. The inside of the flasks was made perfectly smooth so that nothing could prevent the sand from freely falling into the lower container. The neck that connected the two parts of the hourglass was equipped with a special regulating diaphragm. Through its hole, the grains passed evenly and unhindered from the upper part to the lower part.

Time is sand

To make the clock tick more accurately, its main element - sand - was carefully prepared:

• The reddish color scheme of the watch's contents was obtained by burning ordinary sand and processing it through many of the finest strainers. Such sieves did not even give a poorly polished and unground grain of sand a chance to “slip” into the general mass.
• Light-colored sands were obtained from ordinary eggshells. The shell was first carefully selected. After repeated drying and washing, it was roasted. Then it was time for grinding - for the future sand. Pieces of shell were ground several times and passed through the already familiar sieves of fine fractions.
• Lead dust and zinc dust were also used in these watches.
• There are known cases of crushing marble into fine dust to fill hourglasses. Depending on the color of the marble, the contents of the flask were black or white.

Despite the fact that hourglasses showed time more reliably than other types, they also had to be changed. Glass products, perfectly smooth inside, became covered with micro-scratches after some period of time. And, naturally, the accuracy of the watch began to suffer as a result. The most preferable feature for users of this device was the presence of lead-filled watches. Thanks to its uniform grain size, it spoiled the insides of the flask less, which made the watch last longer.

Nowadays, watches filled with loose contents are most often used as interior decoration. And lovers of antiques are hunting for expensive antique models, decorated with precious elements.

By the way, there are some places where the use of this invention did not stop even in the 20th century. Such products counted time in courtrooms. True, they had an automated tipping mechanism. Also, telephone exchanges widely used hourglasses. Because of its short cycle, the watch did an excellent job of telling the time in short phone conversations.

Hourglasses have been used by people since ancient times. This is a fairly accurate device for measuring time, but it has one significant drawback - it can only be used to measure small intervals of time. However, people continue to use hourglasses in everyday life to this day. But if you think about it, the persistence of this image has a lot of reasons.

In fact, an hourglass is the simplest device for keeping time. They do not have a complex mechanism that can break down or begin to malfunction, but they do not depend, for example, on the presence of the sun.
An hourglass of a classic design is two vessels that are connected by a narrow neck, mounted on a stable stand. A certain amount of sand is poured into one of them. Depending on the volume of the vessels themselves, an hourglass can measure intervals of several seconds, minutes or even hours, if we are talking about a large time meter.

How much sand has flown under the bridge since its creation?

There are many versions about how exactly the hourglass was invented. According to one of them, this time meter appeared in Europe around the 8th century. According to this version, the hourglass is the brainchild of the French monk Liutprand from Chartres Cathedral. The next mention of this invention occurs in a fresco dating back to the 14th century. The hourglass was depicted in his work entitled “Allegory of Good Government” by the Italian artist Ambrogio Lorenzetti in 1338. From about this time there are references to these time meters in ship's logs.

For a long time, the hourglass was considered the most practical device of this kind. However, starting around the early 1500s, their popularity began to decline, as most people preferred mechanical watches that came into use, which were more accurate.
Over time, the hourglass has not undergone any significant changes in design. Initially, they were made from two flasks, tied together with a cord or just a thick thread. At the junction, the necks of the vessels were lined with a metal diaphragm with a hole, which precisely regulated the amount and speed of pouring sand. For strength, this joint was also filled with wax or resin to prevent sand from spilling out and moisture from getting inside. The first hourglasses with hermetically sealed bulbs appeared around the 1760s. They were more accurate than the previous analogue, since constant humidity was maintained inside the vessels. As a result, the sand could not become damp, and therefore was always poured at the same speed.
Note that not any sand could get into the hourglass. To obtain a high-quality filler, craftsmen took a fine-grained variety of sand, first burned it and sifted it through a fine sieve, and then dried it thoroughly. The more uniform its grain size was, the more accurate the readings of the finished time meter were.

By the way, the hourglass was filled with granules of various origins. It could be powder from finely ground marble, crushed eggshells, and in some models they tried to use tin or lead oxide. Hourglass makers have conducted many experiments to understand which granules give the most constant flow. There are written references to the fact that there was even a special workshop in Paris that specialized in the preparation of original filler for this time meter. Here it was made from powdered black marble. It was ground into fine sand, boiled in wine and then dried in the sun.
However, it is still impossible to say for sure which granules are the best. Moreover, other factors besides the quality of the sand also influence the accuracy of the readings. For example, its quantity or the size of the flasks and the neck connecting them. When creating hourglasses, the craftsmen experimented a lot with the ratio of their sizes. As a result, it was determined that the diameter of the neck should not exceed half the diameter of the flask. The minimum size of this hole can be equal to 1/12 of the diameter of the flask.

The choice of this indicator depends not least on how large the granules are that fill the hourglass. Accordingly, identical time meters of this kind, differing only in the diameter of the neck, can count different periods of time. The narrower the isthmus connecting the flasks, the longer it takes to pour sand. By the way, over time, hourglasses lose their verified accuracy precisely because due to constant friction, the granules inside the flasks are crushed into smaller ones and, as a result, pour out faster. The quality of the glass is also of great importance. It must be perfectly smooth without any defects inside, so as not to interfere with the free movement of grains of sand.
European hourglasses were typically designed to last from 30 minutes to a full hour. However, there were also instances that measured a 3-hour period of time. It was extremely rare for an hourglass to be created that lasted as long as half a day. However, such a time meter must, without exaggeration, have gigantic dimensions.
For those whose homes could not accommodate such a capital structure, special kits were invented. Several hourglasses were installed in one case at once. Such a device made it possible to measure long time intervals. It was possible to buy similar hourglasses simply folded into one case.

Technological progress did not stand still. He also touched upon the hourglass, which needed improvements in order to compete with any practical and accurate mechanical analogues that had appeared. For example, craftsmen in Nuremberg and Ausburg complicated their design by placing four flask systems in one case at once. A mathematician named De la Hire contributed by creating an hourglass so accurate that it could even measure second intervals. The scientist Tycho Brahe became famous as an astronomer, but he also had a hand in the evolution of this device, trying to replace the usual sand with mercury. Fortunately, such a dangerous innovation did not take root.
However, the biggest breakthrough in this area was made by Stefan Farfler, who created a spring mechanism with which the hourglass automatically overturned at certain intervals. Naturally, this innovation made their use much more convenient.

The evolution of “flasks” into alarm clocks

Before the hourglass came into widespread use, a hydrologium or, as this device is also called, a clepsydra, was used. In fact, this is a water clock that was used by the Assyro-Babylonians and the inhabitants of Ancient Egypt. A clepsydra is a cylindrical vessel with water flowing out of it. Equal intervals of time were noticed on the cylinder. It is with clepsydra that the expression “time is up”, which is still used today, is associated.

The Greeks improved this design. Plato, for example, described a mechanism consisting of a pair of cones entering each other, regulating the speed of water flowing out of vessels. Of course, such specific designs were not very convenient. While they could still be used in production, on ships, where timing was necessary to determine speed, such a clepsydra did not give accurate readings.

In the Middle Ages, the design of water clocks underwent a number of changes, making them more convenient and accurate. The clepsydra turned into a drum, divided inside into several longitudinal chambers with water, inside which there was an axis with a wound rope. The drum was hung by this rope, and it began to rotate, unwinding it. The water inside the clepsydra, flowing from one chamber to another, regulated the rotation speed. Time was counted by lowering the drum.
However, the clepsydra was still far from ideal, since its accuracy continued to depend on the height of the flask, the presence of pitching and the ambient temperature. In winter, the water in such watches could simply freeze, making them completely useless.

The hourglass did not present such unpleasant surprises. People began to use them at home in the kitchen, in church, and then in production. It was the hourglass that measured lunch break times for various employees.

However, it was precisely for sailors that this device, accurate and practical, became a real find. Since the 15th century, any ship had at least three such time meters. One hourglass was designed for four hours, which corresponded to the time of one watch, the second - for a minute, and the third - for 30 seconds. With the help of the latter, the sailors calculated the speed at which the ship was moving along the log.

By the way, this is where the naval tradition of measuring time with “flasks” came from. The watchman, who monitored the readings of the ship's hourglass, regularly struck the ship's bell each time, turning over the half-hour hourglass, that is, in fact, “struck the bells.” After every full hour the sailor rang the bell twice.

The famous navigator Ferdinand Magellan used an hourglass in a set of 18 pieces during his voyage around the world. He needed to know the exact time for navigation, as well as to keep a ship's log. The hourglasses on the ships of this Magellan expedition were designed for 15, 30, 45 minutes and a full hour. Each ship had a person who had to turn them over as necessary. In addition, his duties included reconciling and correcting clock readings.

Of course, these days the Navy uses more advanced instruments for measuring time. However, hourglasses are still used in everyday life. For example, they can be useful in the kitchen as a timer. For the same purpose, hourglasses are used in school laboratories or when testing reading techniques, in treatment rooms. Such time meters are produced for recording intervals when measuring pulse, antipyretic wraps, contrast showers, treatment with mustard plasters or medical cupping. Also, an hourglass, designed for 10 - 15 minutes, is very convenient to control the time spent in a sauna, bathhouse or solarium.

Children will really like this time meter. A bright hourglass filled with colored granules can turn boring hygiene routines like brushing your teeth or dousing during hardening into a fun game.
Already in the twentieth century, hourglasses were used for more serious purposes. For example, models with an automatic tilting mechanism were also used by telephone exchange workers to control the duration of conversations. The hourglass was used during legal debates so that opponents would not have their thoughts wander too much. They are used for the same purpose in both houses of the Australian Parliament. There, the duration of speakers' speeches is limited by a special hourglass with three systems of flasks.

By the way, electronic versions of such time meters have now also appeared. By the way, you can buy such an hourglass not only as an original interior element. They can be very useful in everyday life. For example, the electronic hourglass from designers Fabian Hemmert and Susan Hamman is an unusual alarm clock. You just need to tilt its body 45 degrees, and the function is launched: red LEDs begin to “roll” on the display. It is noteworthy that this alarm clock should be set not to the time of rising, but to the duration of sleep. Each luminous point corresponds to one hour of night dreams. When you wake up at night, you can easily see, even in the dark, how much sleep you still have left. And for those who like to lie down a little longer after the alarm clock has signaled the rise, this so-called hourglass has a special function. Just turn them over - after five minutes they will again remind you that it is time to get up.

However, in the vast majority of cases today, an hourglass can only be bought as an original element of the interior. With the advent of much more accurate mechanical and electronic time meters, their practical function still loses to the aesthetic one. But here the masters can give free rein to their imagination. Hourglasses are placed in cases made of valuable wood, decorated with fancy ornaments. Sometimes they are even inlaid with various precious stones. Such antique table clocks can become the highlight of the interior.

Craftsmen from Thailand did not limit themselves to experiments on the external decoration of watches. They probably remembered that inner beauty is much more important, but they took this statement too literally. As a result, their hourglass was filled with small diamonds instead of the usual sand. The total weight of the precious filling was approximately 10 thousand carats. This hourglass is one of the most expensive today. Their cost is 6.4 million dollars.

It's time for records

As you know, there are no limits to perfection, and therefore masters from different countries are still trying to create the best and most unusual hourglasses. Since in principle there cannot be a complex mechanism in this time meter, and you can’t really do much magic on the shape, all that remains is to experiment with the dimensions.
For example, in the early 90s, an hourglass was created in Hamburg, which is the smallest to date. The height of this masterpiece does not exceed 2.4 cm. Sand is poured from the upper part to the lower part in a period of time equal to 5 seconds.

Creating an hourglass of gigantic size seemed to be a more exciting activity. There has even been some rivalry in this area.
The first such giant has a permanent residence in the Sand Museum located in the Japanese city of Nîmes. This hourglass was created in 1991. Their height is 5 m with a diameter of the flask chambers of 1 m. However, 13 years later, their fame was eclipsed by the popularity of one of the main attractions of Budapest.
As you know, in 2004 Hungary became part of the European Union. For the residents of this country, such an event turned out to be very joyful. In honor of him, a monument known as the “Wheel of Time” was erected in the central part of Budapest, near Heroes’ Square.

This gigantic hourglass has become a symbol of the fusion of ancient traditions and the latest technology. They are equipped with a very complex semi-automatic mechanism, which, using a computer, controls the pouring of sand. However, its complexity is largely due to the size of the time meter. The Budapest hourglass reaches as much as 8 m in height. They are a gigantic granite circle that makes one full revolution during the year. And on December 31, the sand-filled chamber moves upward, and the annual countdown starts again. Moreover, this revolution is carried out not by a computer program, but by a person who, however, uses cables and a simple mechanism to help move a heavy block of stone. Thus, this hourglass symbolizes human perseverance and strength, which has helped us overcome all obstacles for many centuries.
According to the creators, the “Wheel of Time” symbolizes Hungary’s entry into a new era of development.

However, after another four years, this record was broken. In 2008, the German automobile company BMW decided to install a kind of advertising on Red Square in anticipation of the presentation of a new model. As a result, an hourglass appeared in Moscow, the height of which was 12 m. It was made of durable acrylic glass and filled with shiny metal balls. In total, 180 thousand of these balls were used for this clock, resulting in the total weight of the entire structure reaching 40 tons. This hourglass was built over the course of nine days and was supposed to count down time until July 8, 2008 - that’s when the presentation of the new model from BMW was supposed to take place. By the way, the hourglass was so large that, in addition to the metal balls that periodically fell down, the car itself was located in its upper chamber.
It turns out that these days an hourglass is not so much a device for measuring time, but rather an element of style or even an indicator of the high status and good taste of the owner.

Olya

Hourglass. Past, Present and Future.

How it all began.

Before the invention of mechanical watches, clocks used the movement of the sun or simple measuring instruments to keep track of working time. Solar may be the oldest device by definition of time; they are still used in many park areas as a popular accessory that attracts attention, but causes only visual interest, there is no talk of any practical application. Stonehenge, a giant monument built of upright stones on Salisbury Plain in Wiltshire in England, may have been used as a sundial and as a calendar. Sundials have obvious disadvantages; they cannot be used indoors, at night or on cloudy days.

Other simple measuring devices have also been used to determine time intervals. There are four main types of such devices that can be used indoors and regardless of the weather and time of day. Clock candle - This is a candle with lines drawn directly on its body, usually marking the duration of one hour. The time passed was determined by the number of burnt marks. But the candle clock had disadvantages; the determination of time was rather arbitrary; then, the different composition of the wax, the wick, as well as drafts and other factors greatly influenced the burning process of the candle. Clock oil lamp - used in the 18th century, it was an improved version of the candle clock. The point was that there was a scale on the kerosene tank, and during the process of burning it out, time was kept track of. This type of watch was more resistant to environmental influences and materials. Water clock also used to control time, water dripped from one reservoir to another, which was marked with time intervals. Or simply water from the reservoir dripped onto the ground (if water was not saved), the reservoir, as in all previous versions, had a scale. The water clock is also known as the clepsydra.

Story.

They were also used by the ancient Greeks and Romans. The first historical references to the hourglass appear in the 3rd century BC. History also shows that hourglasses were used in the Senate of Ancient Rome, and during speeches the hourglass became smaller and smaller, perhaps as an indicator of the quality of political speeches. In Europe, the first hourglass appeared in the eighth century. By the beginning of the 14th century, hourglasses were widely used in Italy and by the end of the century throughout Europe. The hourglass has the same principle as the clepsydra. Two glass flasks are connected by a narrow neck so that sand (with a relatively uniform grain size) passes from the top flask to the bottom. The glass containers are enclosed in a frame that allows you to easily turn the hourglass over to start a new countdown. Hourglasses are used everywhere, in private homes in kitchens, in churches to control the length of sermons, in university lecture halls, in craft stores. Medical professionals use miniature hourglasses with a duration of half or one minute to measure pulses and other medical procedures, the practice of using such clocks continued until the 19th century.

Material.

Hourglass glass is made from the same material as all other types of blown glass. Sand is the most complex component of an hourglass. Not all types of sand can be used as the grains of sand may be too angular to flow properly through the mouth of the hourglass. Sand from sunny beaches looks tempting, but is not at all suitable for watches, as it is too angular. Marble dust, dust from other rocks, small round grains of sand like river sand are best suited for hourglasses. Interestingly, in the Middle Ages, books for housewives contained recipes for making glue, paints, soap, as well as sand for hourglasses. Perhaps the best sand is not sand at all, but tiny glass balls with a diameter of 40-160 microns. In addition, such glass granules can be made in different colors, which makes it possible to choose an hourglass to match the interior of the room where it will be located.

Design.

Design and concept are usually the most difficult step in hourglass production. A watchmaker must simultaneously be well versed in the world of design, be an artist, have good contact with the public, and also have a good knowledge of production technology. People and companies who order hourglasses want them to reflect their character, business style, and also contain materials related to their products. Once the design development is complete, the actual production of the watch is quite simple.

Hourglasses come in different shapes and sizes, the smallest being the size of a cufflink, and the largest measuring 1 meter. Sand ones can have almost round, oblong flasks, or they can contain not two of them, but form cascades. The hourglass figure is very popular.

Production process.

Once the design and choice of materials have been decided, the body of the hourglass is blown on a glass lathe to a size that matches the size of the hourglass time slot. The watch frame allows for the possibility of imagination and can be made from many materials nowadays. One of the biggest misconceptions is that there is a formula for determining the amount of sand contained in a watch. The amount of sand in an hourglass cannot be analyzed or calculated. The type of sand grains, the roughness of the glass, and the design and shape of the hole impose too many variables to determine the speed of sand passing through the mouth of the hourglass such that the amount of sand cannot be calculated mathematically. The process is like this before To seal the top flask, sand is added to it and passed through the neck of the hourglass in an amount corresponding to the prescribed time interval. After completion of the calculated period of time, the sand remaining in the upper part of the flask is poured out and the flask is sealed. The customer is a full participant in production, because all his wishes are taken into account and strictly implemented. The end result is that customers receive handcrafted products that meet their requirements and evoke historical and artistic associations. An hourglass is an aesthetic decoration and not an accurate timepiece.

Future and Hourglass.

Hourglass, it would seem, has no future. In fact, the beautiful shape of the glass flask itself, the elegantly crafted frame, and the color of the sand can perfectly complement the interior and describe any incident in life. Of course, the sand clock may not be mass produced, but for connoisseurs of time, beauty, and collectors, such an object will always be desirable.

The hourglass is one of the most ancient inventions of mankind., but the exact date, unfortunately, is not known. However, according to the data that have been preserved, we can conclude that the principle used in the hourglass was known in Asia long before the advent of our chronology. Despite the fact that in our time watch mechanisms are actively developing, hourglasses are still actively used.

Hourglass in the Middle Ages

It was the Middle Ages that made the biggest leap in the development of the history of the hourglass.. One of the oldest references to clocks comes from the 14th century, which contains advice on preparing special, fine sand for use in hourglasses.

The hourglass appeared in Europe quite late, but, despite this, they quickly came into use by almost every person, this was facilitated by their low price, ease of use, reliability, and most importantly, the ability to measure time regardless of the time of day, this distinguished them favorably from sundials.

The most common clocks had one significant drawback - it was a relatively short interval, an hour or half an hour. It was rare to see a watch that could measure 3 hours, and very few were designed for a relatively long hourglass operating time. These were huge, bulky structures that could count 12-hour intervals.

Hourglass production

The most important thing for the accuracy of the hourglass was the quality of the sand., it must be sifted through numerous sieves, thoroughly dried and annealed. Glass flasks for making watches were produced using well-known technology. A plate was inserted into the place where the flasks were joined, which was supposed to regulate the pouring speed. To hold the two flasks together, the junction between them was tightly wrapped with thread and additionally covered with resin.

The shape of the flasks and the quality of their surface were also important for the accuracy of the stroke. When the hourglass was used for a very long time, its accuracy deteriorated. This was due to the fact that the inside of the flask was gradually scratched by sand, and the fact that the sand was crushed into smaller fractions also played a big role.

Hourglass - photo

We present to you photos of various hourglass shapes.

Hourglass meaning

The hourglass is a symbol that reminds us of moderation., that time is fleeting, and there is no need for the allotted time to be shortened by excesses. The two vessels represent cyclicality, the alternation of life and death, chaos and order.

Certainly, You won’t be able to get far away from the classic hourglass shape., because two interconnected bulbs and a frame are the basis of such a watch. But you can change the very shape of the flasks and the frame supporting them to whatever you want. For example, an excellent gift in business circles is an hourglass whose flask is the company logo. There is also the opportunity to experiment with materials: colored glass, stones of various types, wood, metals (possibly even precious) can make an hourglass unique in its own way.

The world's largest hourglass is 11.9 meters high, and their cycle is 1 year, it is the greatest device for measuring time. This watch could be seen in Moscow, on Red Square in July 2008. The smallest watch, only 2.5 cm high, was created in Germany, in Hamburg; sand pours out of the top flask of this watch in just 5 seconds.

Even though hourglasses have flaws and are not the most accurate, they were used even after the invention of mechanical clocks, in the 20th century they were used in telephone exchanges and in courtrooms.

Nowadays, hourglasses play more of a decorative role., as interior design elements. This ancient invention is also used during some medical procedures.

Hourglasses are one of the most ancient types of devices invented by people to measure time.

Despite the active development of watchmaking and the emergence of more advanced mechanisms, hourglasses are still used today.

Start

The history of the origin of the hourglass lacks specifics and reliably confirmed facts, however, based on surviving sources, it can be assumed that the principle of constructing such a device was known in Asia even before the birth of Christ. Despite the fact that bottle clocks were mentioned by Archimedes, and the first attempts to invent glass were made in Ancient Rome, during Antiquity no one was able (or perhaps did not want to try) to make an hourglass.

Middle Ages

The next milestone in the history of the hourglass was the Middle Ages. At that time, craftsmen who were working on improving water and solar grandfather clocks also took up bottle designs. Due to their low cost and ease of use, they immediately gained incredible popularity.

One of the first European hourglass models was made in Paris. A record of this dated back to 1339, and the text of the message contained instructions regarding the preparation of fine sand (for this, black marble powder, previously boiled in wine and dried in the sun, was sifted). The quality of the sand was one of the fundamental factors on which the accuracy of the watch depended: in addition to marble, grayish sand from zinc and lead dust, reddish fine-grained sifted sand, and light white sand from fried ground eggshells were used. The grain size and flowability of the sand had to be uniform.

Most often, sand was poured with the expectation that the clock would work for thirty minutes or an hour, but there were also models that worked for three and even twelve hours.

Developments in transparent glass production technology were used to produce the case elements of hourglasses, mantelpieces and chiming wall clocks. For bottle clocks it was converted into spherical flasks.

For maximum precision, the glass had to be smooth, without defects. In the place where the neck of the vessel narrowed, a horizontal metal diaphragm was placed, the opening of which served to regulate the quantity and speed of pouring grains of sand. At the junction, the structure was tied with thick thread and fixed with resin. Unfortunately, medieval craftsmen were never able to make an hourglass that would be as accurate as a sunglass: with prolonged use, the grains of sand gradually became crushed, and the hole in the diaphragm expanded, thereby accelerating the passage of sand.

New time

With the advent of interior watches, as well as women's and men's mechanical watches, the hourglass had to be improved so that it could compete with more accurate time measuring devices. For this purpose, the production of hourglasses began in the cities of Augsburg and Nuremberg, the design of which consisted of four systems of flasks in one case. At the same time, the mathematician De la Hire created an hourglass capable of measuring second intervals. Attempts to replace sand with mercury were made by astronomer Tycho Brahe. However, the last two innovations were not as significant as Stephane Farfler's invention of a spring mechanism, which ensured automatic tilting of the watch.

20th century and modern times

Even though hourglasses are not the most accurate and have some disadvantages, they continued to be used well into the 20th century. Hourglasses with an automatic tilting mechanism were used in the courtroom, as well as in telephone exchanges (to control the time of short telephone conversations).

At the present stage, antique hourglasses can serve as a decorative element, and models encrusted with diamonds are especially popular among collectors. And finally, a bottle-shaped electronic watch, on the screen of which not grains of sand, but pixels are scattered, reminds us of the history of the development of watches.