Among the many watches, regarding the difficulty of operation and use, I thought that the Rolex Yacht II was the highest. Most watch friends did not know that it could not only be equipped with a timing function, but also can be rotated. Set the ‘Countdown’ setting. But recently, we got another watch, and found that it is more difficult to use than Yacht II, which is called the ‘ultimate IQ test’. It is Lindbergh’s ‘White Angle’ watch from Longines. It is more important to be a person to find your own position, and it is also important for ships drifting in the vast sea. In 1707, the British Royal Navy defeated the French Navy’s rear division and returned to the North. However, it struck the reef in the Isles of Scilly, 45 kilometers away from the British mainland, killing 4 ships and the 1,400 to 2000 sailors on it. This is the history of the Royal Navy. One of the greatest disasters. In addition to bad weather, the inability of the navigator to determine the exact location of the ship was also responsible for the disaster. As long-distance navigation becomes more frequent, the importance of reliable navigation becomes more important. The Isles of Scilly Islands event eventually led to the passing of the famous Longitude Act in 1714, which provided incentives for those who could find an accurate way to determine the longitude at sea, up to 20,000 pounds at the time, which is equivalent to more than 26 million yuan. And the easiest way to determine the accuracy at sea is to pass the time. Usually, we set the day to 24 hours, and the earth’s circle is 360 °, which means that 1 ° means 4 minutes. As long as we know the standard time at Greenwich Observatory on the 0 ° meridian and the current time at the location, we can convert the longitude at the location. In 1927, American Charles A. Lindbergh flew from New York to the Atlantic Ocean to Paris, becoming the first person in history. Later, he made suggestions to Longines based on the rapid positioning problems in his personal experience, and sent the design drawings to John Heinmüller at the end of 1930. John Heinmüller is not only the chairman of the International Aviation Federation, but also a director of Longines-Wittnauer in the United States. Just 5 months later, the first prototype watch was produced, and later this year, this hour watch called ‘Hour Angle’ was in production. Because it was designed by Lindbergh, it is often called ‘Lin Bai’ in the workshop. The reason why this Lin Bai watch can help pilots quickly determine the longitude of the location is also dependent on time. There are different scales on the outer ring and dial of the forest watch, which need to be used together with the hands. For example, the points marked in green correspond to the scale of the green portion of the outer circle; the marks marked in blue correspond to the scale of the blue portion on the outside of the dial; the seconds marked in red correspond to the scale of the red portion on the inside of the dial. Assume that the time shown in the figure above at 10: 8: 40 is the current GMT standard time on the 0 ° meridian, that is, the corresponding scale is 150 ° + 2 ° + 9 ′ = 152 ° 9 ′. At the same time we assume that the time at our location is now 9: 4: 0, and the corresponding scale is 135 ° + 1 ° + 0 ′ = 136 ° 0 ′. Then we subtract the angles at the two scales, 152 ° 9′-136 ° = 16 ° 9 ′. If the result is positive, it means west longitude, and the result is negative, it means east longitude. Using another sextant to determine latitude, we can know where we are currently on the Atlantic Ocean. Seeing this, it is estimated that many cousins have already passed out, but this is not over yet! !! !! Earlier, we said that the day is usually set to 24 hours, and the earth is 360 °, which means that 1 ° means 4 minutes. On the equator, for every 1 ° difference in longitude, the actual distance is 111 kilometers. Converted to it, the watch is almost 4500 meters in one second. Therefore, in addition to the precise display of the hour and minute hands, the second hand is also important. The distance of 4,500 meters is enough to cause a recurrence of the incident on the Sili Islands. Therefore, in the era of big sailing, the accurate navigation clock is the most important equipment on board. It is supervised by a special person, and it must be readjusted according to the standard time of the observatory before going out to sea. Now our watches usually have a ‘stop second’ function, that is, pull out the crown, the second hand will stop moving at the same time, so that we can adjust the time, and even some models of Lange, Glashütte also have a ‘stop zero’ Function, more practical. But at the beginning of the last century, the stop-second function was not available on pocket watches or watches, and it was very troublesome to adjust the time each time. In 1927, the US Navy Major P. Van Horn Weems developed a series of navigation instruments called the ‘Weems Navigation System.’ In his invention, although the second hand could not be adjusted, it turned the dial of the second hand into a dial that can be adjusted forward and backward. In this way, no matter the second hand is moving at any position, it is only necessary to align the zero dial of the rotating dial with the second hand, which is equivalent to the second hand moving from zero at this time. (The hour and minute hands read the time according to a fixed scale, and the second hand reads the time on the rotary dial. The two are independent and then added together.) Based on this, Major Weems cooperated with Longines to design a A dial watch that enables users to synchronize the second hand with the GMT time broadcast signal, namely: Longines Weems Second-Setting Watch, which was patented in 1935. The pilot Charles A. Lindbergh upgraded and improved the second hand setting watch based on Major Weems, solving the problem of not being able to “stop the time”, and evolved into the famous “Linbai” navigation watch. The crown is used for manual winding in the first position; the silver small dial can be adjusted back and forth separately when pulled out to the second position. This silver small dial is used to match the seconds with the corresponding reading time and the longitude angle; The third gear is used to adjust the hour and minute hands. Talking here, in fact, the use of the Lin Bai watch has not been completely finished. As mentioned earlier, the Lindbergh watch relies on time to help pilots quickly determine the longitude of the location. Usually we say that a day is 24 hours, but in fact the orbit of the earth around the sun is not a circle, but like a gourd. At the perihelion, the day and night on the earth is actually 23 hours and 44 minutes; at the distant point, the day and night is 24 hours and 14 minutes. We call such time ‘True Solar Time’. Therefore, before relying on the aforementioned method to determine latitude and longitude, we must first convert Greenwich time to ‘true solar time’, and the specific method is to rotate the outer ring of the Lindbergh watch according to the table data. Finally, we summarize how to use the Lin Bai watch:
- Set the second and third gears to the exact Greenwich Mean Time and the time at the time, accurate to the second. Convert Greenwich Mean Time to ‘True Solar Time’ based on tabular data. Compare Greenwich hour and local hour according to the scale, and convert the specific longitude.
Unless other conditions remain the same, the larger the movement’s size, the more accurate the clock will travel. So the first version of the Lin Bai watch was actually based on a huge pocket watch modification. In the pocket watch era, in order to protect against dust and engraving, the case back was often double-layered. During World War I, in the transition period from pocket watches to watches, most of the early watches were actually converted from pocket pocket watches with double hinged back covers. At the same time, only high-ranking personnel such as generals and officers would be dispensed at that time, so the watch with this double-layered back cover was called ‘the bottom of the officer’ in Chinese. The original antique Lin Bai watch had a general bottom cover, and Longines also retained this design, engraved with the ‘flying hourglass’ logo that the brand has used since 1687. At the push of a button, you can open the bottom cover to see the built-in mechanical movement Cal.989. Longines Cal. 990 movement, the representative model of Longines ultra-thin movement, Cal. 989 is based on Cal. 990 alone for Longin’s Lin Bai watch, can adjust the small dial. The Cal.990 movement was born in 1977. It uses side-by-side double springs to replace the overlapping double-spring design of the Cal.890 movement. The thickness of the movement has been reduced by almost half to 2.95 mm. Later, Lemania acquired the design and production rights of L990, and launched Lemania 8810 and improved versions 8815, 8881, 8840, and 8860. And finally belonged to the Swatch Group, and now we can find this movement on the watch brand Breguet. In addition to being a watch that tests IQ, Longines Linbai has witnessed the change of the Longines brand. During the quartz crisis, Longines and Omega made all watches, which caused the product line to be too long and was seriously dragged down as a result. At the worst time, even these two brands were to be sold to the Japanese consortium. In order to save everything, Swatch President Hayek made the decision at the time to ‘raise the Omega brand, lower Longines, and maintain Tissot’, and eventually Cal.990 was forced to stop production. At the same time, Longines’ movement production research and development department was divested and merged into the ETA movement factory, so Cal.990 is the brand’s last self-produced mechanical movement, known as ‘Longines must sing!’