Main menus within website
We introduce a wide range of trivia (bits of knowledge) about time, from the history and culture of
time and timepieces to their types, mechanisms, terms and concepts. This offers such an exiting feeling
that you will be surprised by this new knowledge and want to share it.
The Secret of the Clocks that Always Read 10:08:42
When you see a catalog or brochure for Seiko analog watches and clocks, all of the hands appearing in it indicate 10:08:42. Did you know that?
Looking at some advertisements published by the other companies, you will see their hands also show an identical time for each company, such as 10:06:37, 10:07:37, 10:08:36, or 10:09:35.
Seiko has used 10:08:42 since 1964, before which 10:10:30 was used. This change was caused by the fact that publicity department personnel working at that time were influenced by the sizzle feeling, which was an ad expression used in the U.S. that means a mouthwatering feeling and freshness when it comes to food advertisements. Some say that the publicity department wondered, “How can we make customers feel the clock’s movement only by looking at our advertisements?” when they looked at a mouthwatering steak ad and kept thinking until deciding on the time of 10:08:42, which expresses a sense of dynamism.
Even today Seiko is using this rule, because this watch and clock hand layout not only expresses a sense of dynamism, but also has the following advantages: (1) the three hands are not overlapping, (2) they look beautiful and firm, and (3) the brand name placed under the 12:00 letter is visible.
(“K. Hattori & Co., Ltd. Sales and Marketing List,” September 16, 1902)
The Mystery of Numerical Notation on the Dial Plate - 4 is Expressed as IIII, not IV
The numerical notation of 4 is IV in Roman numerals. You probably think so, too.
However, there are many cases where IIII is used at the 4:00 position on the dial plates of clocks that use Roman numerals.
There are a variety of theories about this.
One holds that in the late 14th century, Charles V, the king of France, told a watchmaker to change IV to IIII, because he considered IV to be bad luck as it was created by subtracting 1 (I) from his title 5 (V). The notation IIII was used for the clock at the earliest Wells Cathedral, which was built at the end of the 14th century in England, and has been conventional since then. Somebody thought IV was not easily understandable because it resembled VI and was also well balanced with VIII, which was placed in its symmetrical position. In the middle ages in Europe, IIII was generally used, not IV, to express the Roman numeral 4 until around the 17th century.
In fact, you can see the notation IIII on mechanical turret clocks that were made before around the 17th century. The most popular theory is that the notation IIII has become conventional in the industry because it looked well balanced on the radial dial plate design and has remained on clocks and watches ever since.
Even the clock numbers you are familiar with have an unexpected history. See how 4 is notated on the clocks using Roman numbers around you.
The Big Role of the Tiny Magic Lever
The Magic Lever, a scissors-shaped tiny part contained in self-winding wristwatches, was developed by Seiko in 1959. It has the important role of efficient winding of mainspring, by converting the rotary motion of the rotor in a self-winding wristwatch, which is generated by the arm’s movement, into vertical motion. The following describes its mechanism.
One key point of the Magic Lever is that its shaft is on an eccentric pin that is outside of the central shaft of the rotor. Therefore, the Magic Lever itself always moves up or down regardless of whether the rotor turns clockwise or anticlockwise.
Also, the Magic Laver has two spring pullets of different shapes. The tips of those two pullets pull pullet (A) and push pullet (B), are always kept in contact with the transmission wheel, which is used to rotate the barrel wheel containing the mainspring, by the spring’s force. When the Magic Lever moves down, this spring’s force makes the tip of pull pullet (A) pull and rotate the transmission wheel and push pullet (B) slides down the slope of the gear teeth.
On the other hand, when the Magic Lever moves up, the spring’s force makes the tip of push pullet (B) push and rotate the transmission wheel and pull tab (A) slides up the slope of the gear teeth.
As described above, regardless of the rotational direction of the rotor, the two pullets of the Magic Lever always generate a unidirectional movement and also make the transmission wheel always rotate in one direction, which enables efficient winding of the mainspring.
What do you think of the big role of the tiny Magic Lever? The Magic Lever is an important core part of Seiko's unique self-winding mechanism, which has dramatically increased the winding efficiency, and has been used in most self-winding mechanical watches produced by Seiko.
Why are Stones Required in Watches?
When you look at a catalog of mechanical watches, you will see the description of the number of stones. How are watches and stones related? As a matter of fact, a stone is one of the important parts in watches.
In the movement (machinery system) of a mechanical watch, the parts with a vertical shaft, such as gear wheels and balance wheel, are secured between the base plate at the bottom and the bridge at the top. It is like the parts are sandwiched between the base plate and the bridge, supported by their shafts.
The shafts execute rotary or back-and-forth movement while being in contact with the bridge and the base plate at the top and bottom, respectively. Therefore, the areas with which the shafts are in contact are required to withstand wear so as not to reduce their accuracies or fail.
To achieve this, a stone is used as an end. A synthetic ruby, sapphire, or other hard stone are used, which are durable enough to have a high friction resistance. By covering it with oil for protection, the gear wheels and other parts move accurately at all times while the oil is retained for a long time. There are some cases where the escape wheel and balance wheel use four stones, which have two hole stones around the shaft, and two cap stone, which have no holes, at the top and bottom, respectively. In addition to the shafts, synthetic jewels are used as stones for the pallet folks, and impulse pin which wear easily.
Generally speaking, more stones are required in higher-class and more complicated mechanical watches although minimum 17 stones are good enough for functionality. For example, Grand Seiko High Beat uses 37 stones.
Colored Woodcut Depicting Timepieces
We introduce you ukiyo-e prints, which capture society during the period of rapid Westernization, from the Edo period to the Meiji period.
"Injun Kaika Ryuko Gekkenkai," drawn by Ikkei Shosai (Giboku Shosai) and published by Manson, is a colored woodcut from a three-sheet series from the early Meiji period.
It depicts Japanese objects used since ancient times and foreign objects newly introduced from the West. It portrays scenes of sword fighting and partisan fighting in an attempt to determine which is more popular.
The print in the upper right portrays the traditional Japanese clock being knocked down by the latest octagonal clock (Western clock) near Narita Fudoson.
Other objects drawn for comparison include a kotatsu and a heater, komageta (Japanese clogs) and shoes, kabuto (Japanese armor) and a hat, cattle and fighting cocks, a crepe and velvet.
Unfortunately, such Japanese objects became obsolete, but it is interesting to view a slice of life from that time.
Which Day is the Beginning of the Week?
Which day is the beginning of the week, Sunday or Monday?
The Gregorian calendar, currently used in most countries, is derived from the Hebrew calendar, where Sunday is considered the beginning of the week. Although in Judaism the Sabbath is on Saturday, while in Christianity it is on Sunday, Sunday is considered the beginning of the week in both religious traditions. Because Sunday is the beginning of the week culturally and historically, many calendars follow this rule.
Currently, a five-day workweek has been well-established worldwide and most people consider Saturday and Sunday to be the weekend. In that case, it is more practical to consider Monday, the end of the break and the start of work, as the beginning of the week.
In fact, in 1971, rules were established that Monday was considered the beginning of the week in daily life and business practices, recommended by the ISO (International Organization for Standardization). Accordingly, Monday through Sunday are indicated by numbers, 1 to 7.
A new method of specifying the date by week number and day number has been utilized since then, which is why some European calendars regard Monday as the beginning of the week.
There is no wrong answer in this debate. However, it is important to be aware that if you say, "Sunday this week" or "Sunday next week" in the office or at home, the other party might have a different opinion.
How to Adjust the Time
Today most timepieces are quartz type, which loses or advances only a few seconds per month. Therefore, there is no need to adjust them daily. Radio wave controlled watches and GPS watches, which are adjusted by atomic clock, are more convenient. Nevertheless, such timepieces powered by motors may stop temporarily or display the incorrect time due to the impact of magnetic fields, such as from magnets. If you notice the second hand lose or advance a few seconds, take the following steps to adjust the time.
- 1. Pull the crown and stop the second hand at the 12:00 position. (For screw lock-type watches, turn the crown to the left to loosen the screw, and then pull.)
- 2. Turn the crown and move the minute hand to adjust the time. In the case of quartz watches, first advance the minute hand by 5 to 10 minutes, and then reverse to adjust the time. This will prevent a gap in the hand caused by backlash of the gear trains.
- 3. Push in the crown at the same time as the time signal (In the case of screw lock-type watches, screw it in until they stop to the right while pressing the crown.)
Please note that the instructions for adjusting the time in the case of mechanical watches differ from quartz watches, which will be explained later.
"5 SPORTS Speed-Timer" 6139, a Wristwatch that Experienced Space Travel, the First Automatic Chronograph
On November 16, 1973, when Mr. William Pogue, a NASA astronaut, boarded the Saturn IB rocket, he put a Seiko wristwatch in the pocket of his space suit.
The watch was a Caliber 6139 Seiko "5 SPORTS Speed-Timer," the world’s first automatic chronograph, which Seiko launched in the spring of 1969. Mr. Pogue purchased it for 71 dollars at that time at a kiosk in the air base.
Seiko watches were not officially approved by NASA. However, when flight training started, official watches were not yet distributed to astronauts. Therefore, Mr. Pogue did flight training while wearing a Seiko. “I found this Seiko to be very convenient when measuring the burn time of a rocket engine using the rotating bezel,” he said. Mr. Pogue wanted to use the Seiko in space as well, and decided to carry it with him on the mission in his personal belongings. On the space station, he completed his assignments wearing the NASA official wristwatch on his right wrist and the Seiko on his left.
Because of the highly efficient automatic winding performance, the Caliber 6139 did not have a manual winding mechanism. Even though it did not have the specifications to withstand the space environment, the oscillating weight was rotated when he moved his arm, and kept time accurately even in the weightlessness of space.
The wristwatch selected by Mr. Pogue had a bright yellow dial. Nearly 50 years since its release, the vivid design remains contemporary-looking and attractive.
Mr. Pogue made 1,214 revolutions around the Earth on that Skylab 4 mission, and completed his assignments at the space station for 84 days, which was the record for being in space at that time. Mr. Pogue cherished his wristwatch for many years after he took off his space suit, but in 2008 he decided to put it up for auction. He donated the money to the Astronaut Scholarship Foundation, a foundation for the development of astronauts.
Source: Heritage Auctions - Official Site 2008
How to Understand the Direction with an Analog Watch
If you lose your way while walking on a mountain or in town, did you know that there is a way to find the cardinal direction south using the sun and an analog watch?
The sun is at its highest position due south at 12:00, which refers to the sun crossing the meridian. Take advantage of this phenomenon.
First turn the hour hand toward the direction of the sun while maintaining your watch horizontally. At this time the angle bisecting the hour hand and the 12:00 position on the dial will show south.
Think of the hour hand as the position of the sun on a sundial. In the case of a watch with a 24-hour hand, which makes one revolution in 24 hours, the 12:00 position of the dial is always south.
In the case of a regular watch, the hour hand makes one revolution in 12 hours, which means that it rotates twice as fast as the sun, because the sun makes one revolution in 24 hours. Therefore, it is necessary to correct this by halving, and the half angle indicates the direction south.
Note that the left side of the dial is south in the morning, and the right side of the dial is south in the afternoon.
In fact, crossing the meridian at Akashi, in Japan Standard Time, is regarded as 12:00 in Japan, which creates an error in other regions. It is also difficult to correctly turn the hour hand in the direction of the sun, so please use this method only as a reference.
Remember that the position, which is half of the 12:00 position and the hour hand is north, instead of south in the Southern Hemisphere.