Marine Chronometers are highly accurate clocks kept aboard ships to aid in navigation. The chronometer is set to Greenwich time. When the time of this clock is compared with the local time at sea a ship's navigator can determine the longitude at that position. As a result, it is important that such clocks keep accurate time amid variations in temperature, humidity and the motions of the sea.) and during my business trip to Taipei, I have finally managed to find one vintage Hamilton World War II Marine clock used by the US Navy.
Background:
At the outbreak of W.W. II the United States Navy required high quality chronometers in large quantities at a time when very few chronometers were being manufactured in the country. The Hamilton Watch Company was the only firm able to meet the challenge by designing and producing an innovative marine chronometer in a period of about 18 months. Hamilton was able to produce the unit in sufficient numbers to meet U.S. wartime demand. Further, the model 21 and later type 22 is technically probably one of the greatest achievements in the history of horology. The balance and hairspring assembly represented a radical departure from traditional chronometer design and resulted in phenomenal time keeping rates. Hamilton made 11,239 of these chronometers during the War.
The Hamilton Model 22 is a legendary watch, hurridly designed when the USA was entering WWII, along with the far more complicated Model 21 marine chronometer; both are considered amongst the finest of their type. The 22 was even produced in the boxed-and-gymbaled format, so it was thought reliable enough to serve as a ship's primary timekeeper! The case is 70mm across, of plated and matted brass, and features a wonderful guarded crown and button to prevent inadvertent setting. Although the mainspring's power reserve is some 60 hours, and the dial indicates up to 48, it was intended that the watch would be wound each day at the same time for nearly perfect isochronism
This is a lucky clock as it has survuved the omslaught of the WWII battle..
http://www.nawcc.org/museum/nwcm/galleries/marine/marine.htm
Some other facts:
In 1939, the US Navy entreated the eight best American manufacturers to make it marine chronometers. In 1941, Hamilton was contracted to produce 337 of them, taking over from Ulysse Nardin who was the main supplier.
On receipt of the first two chronometers, their commissioners leapt with joy: they were excellent. Suddenly, Hamilton was asked to make not 337 but 1,000 pieces. The warships, heavy cruisers and submarines were swiftly supplied with several Hamilton gimbal chronometers stored in their chests.
So pleased were the Americans that demand grew and grew. President Roosevelt, the recipient of a Hamilton marine chronometer, promised in writing that he would take care of it and keep it at the White House until the end of the war, afterwards finding a place for it in his library in Hyde Park. Hamilton met with universal approval, especially since the US Navy had approached Elgin and Roth Brothers and found that their chronometers were not up to the task.
On the other hand, Elgin was developing a diver's watch at the same time as Hamilton. It was a waterproof version of the General Purpose Wrist Watch, featuring a waterproof cabochon winding crown, held by a chain. Hamilton would produce no fewer than 8,902 watches for Uncle Sam's Marines, plus 898 for the Maritime Commission and others. The Hamilton watches of the marine riflemen were engraved with the letters US MC and were, of course, part of their kit. The Germans of the Kriegsmarine had Berg, Alpina, Siegerin and a few Panerai watches, which had a white dial marked KM. The Royal Navy used Jaeger-LeCoultre, Hamilton, Omega, Longines while the Japanese Imperial Navy was supplied by Seiko.
http://www.worldtempus.com/en/encyclopedia/index-encyclopedia/watches-and-clocks/military-watches/
