As the United States marks the 60th anniversary of its entry into World War II, there is a story from that conflict worth retelling. It is the tale of a watch company in Pennsylvania’s Amish farm country, whose accurate timekeepers were essential to the Allied Forces’ victories. It is the story of how Hamilton Watch Co. (today owned by The Swatch Group) helped win World War II.
Renowned accuracy. Hamilton’s wartime contributions took many forms, but most obvious to the nation’s sons and daughters in uniform were its watches, long known for their accuracy. That aspect of Hamilton’s World War II story actually began 50 years earlier.
In 1891, an engineer’s inaccurate pocket watch led to a terrible train crash near Cleveland, Ohio. Afterward, an industry commission devised standards of precise timekeeping for pocket watches (there were no wristwatches yet) used by railroad personnel. Those meeting those exacting requirements were known as “railroad watches,” and a leader in making them was Hamilton, incorporated in late 1892 in Lancaster, Pa. Hamilton’s watches, first produced in March 1894, became so highly regarded for their precision they were nicknamed the “Watch of Railroad Accuracy.”
That reputation took Hamilton into World War I as the official watch of the American Expeditionary Forces. In the 1930s, its wristwatches’ accuracy led several new airlines to adopt Hamilton as their official timepiece.
By 1940, Hamilton was one of America’s best-selling watch brands. It had its own designers, engineers, physicists, and metallurgists and was a leader in horological research in watch oils, hairsprings, jewel bearings, and escapement design.
Then came Dec. 7, 1941, and the Japanese surprise attack on the U.S. Pacific Fleet at Pearl Harbor, Hawaii, followed by America’s declaration of war on Dec. 8.
Wartime demands. Within a year, virtually all American industries—including U.S. watchmakers like Hamilton, Bulova, Waltham, and Elgin—had converted to war service.
“Timekeeping and measuring devices were of critical importance” to military planning and missions and the war effort generally, says René Rondeau, a leading authority on Hamilton watches. Watchmakers made a variety of wartime timekeeping devices. Hamilton, for example, produced top-secret mechanical time fuzes for exact timing of anti-aircraft fire, jewel bearings, hairsprings, aircraft clocks, elapsed time clocks, altimeters, tachometers, map measurers—even tools, dies, and precision machinery for other watch, instrument, and jewel makers.
Demand for war-related time products ended almost all consumer watch business for Hamilton and other American watchmakers for the duration of the war. In fact, they were forbidden by federal order from using critical materials or facilities to make new “civilian watches,” except railroad watches and special timekeeping instruments.
But U.S. watchmakers did make wristwatches for the military. Hamilton alone produced hundreds of thousands during the war—for the Army, Navy, Air Force, other military sections, and for U.S. allies including the Canadians, the English, and the Russians.
These included “hack” watches, named for a mechanism in the movement, connected to the crown, which set time to the exact second. These were used to synchronize countless military attacks, troop and train movements, bombing raids, even training.
Other Hamilton timepieces included the top-secret Frogman watch (for Navy divers), with a large “crown” over the regular crown to keep it watertight; a “Standard Ordnance Issue” model with white dial and second hand at 6 o’clock, used by Army Ordnance and the Russian army and medical corps; and one with a center sweep second hand, used primarily by pilots, including Canadian Air Force pilots. A variation was made for the U.S. Marines.
In the air, pilots and navigators of fighters, bombers, and even blimps used the “4992B” navigation pocket watch (also used by coast artillery) as their “master time source.” This military version of Hamilton’s railroad watch was kept on simple rubber or spring shock absorbers in a small metal carrying case (to isolate it from magnetic fields, vibrations, and turbulence) with a glass window. “It was essential to navigation, and every navigator on every plane had one,” says Rondeau.
Also essential was Hamilton’s “bomb timer”—a wristwatch movement and dial mounted into a bombsight with a movie camera, which filmed the dial and target at the moment of impact to measure the effectiveness of the bombs.
Chronometers needed. Hamilton’s most important achievements in World War II were its marine chronometer and chronometer watches. Indeed, its marine chronometer is considered by many horological experts to be the finest ever produced. What makes that accolade even more impressive is the fact that, until World War II, Hamilton had never made such a timepiece.
Chronometers were must-have naval equipment because precise timekeeping is essential to ship’s navigators in calculating longitude and plotting location and direction. “Without exact time,” says Rondeau, “an error of a few seconds can put a ship miles off course.”
The war in Europe, which began in 1939, forced the U.S. military to consider its critical need for these timekeepers—especially in light of the “acute chronometer shortage” that plagued U.S. forces during World War I, notes Steve Dick, historian of the U.S. Naval Observatory.
A cessation of America’s supply of marine chronometers and chronometer parts—available at that time only from Europe—seemed likely. Germany, a world leader in watchmaking, was one of the belligerents and certainly wouldn’t provide them. Swiss watchmaker Ulysse Nardin was a leading provider to the U.S. Navy, but Switzerland was surrounded by war, its neutrality held captive by the whims of the combatants.
England also produced chronometers, but it was under Nazi air attack, with the outcome uncertain. Moreover, the maritime needs of England’s Admiralty prevented it from supplying the United States.
Even if Europe’s supply of marine chronometers had continued at prewar levels, it wouldn’t have been enough. The U.S. military needed thousands, but prewar production was slow and expensive. The annual output of England and Switzerland combined was only 300 to 400 units—for all world markets.
Studying the problem. So, the U.S. military knew it had a big problem: It needed a reliable high-volume source of marine chronometers, but no U.S. watchmaker made them.
Many American watch firms, however, did mass-produce high-quality pocket watches and wristwatches. So, in mid-1939 and again on June 26, 1940, the United States Naval Observatory (the U.S. authority on timekeeping, chronometers, and other navigational equipment) sent letters to eight watch companies, inviting them to create American marine chronometers. Hamilton replied on July 2, expressing interest and requesting a sample chronometer for study. After deliberation by its experts and officials, Hamilton agreed on Feb. 26, 1941, to tackle the project.
Over the next months, the engineers, technicians, and watchmakers in Hamilton’s Research and Work laboratories and Product and Equipment Design sections studied chronometers, the Nardin model, and maritime and military needs. Then they applied their own insights and expertise to develop new and improved models and testing apparatus more stringent than the USNO’s. Meanwhile, Hamilton’s Mechanical Department created the dies, tools, and equipment to produce the new timekeepers.
On Feb. 27, 1942, 13 weeks after Pearl Harbor and exactly a year after it had begun the project, Hamilton Watch Co. delivered two prototypes for review to the U.S. Naval Observatory in Washington, D.C. USNO officials were “simply astonished,” says Rondeau, by their precision, innovations, and reproducibility.
An amazing achievement. Hamilton’s marine chronometer (Model 21) was based on traditional ones but with several improvements. Most evident was a unique balance and hairspring assembly, a radical departure from traditional chronometer design. According to the late Marvin E. Whitney, the preeminent authority on military timepieces, this new assembly “resulted in phenomenal timekeeping rates.” Also noteworthy was the modified detent escapement.
Such improvements made Model 21 more accurate than any other marine chronometer. In fact, horological expert and former British Museum curator Richard Good called it the most accurate portable mechanical timepiece ever made. Properly maintained, it kept time to within a half-second per day. (The Navy requirement, says Dick, was no more than 1.55 seconds.)
Just as important, Hamilton’s marine chronometer was the first to be designed for mass production using that most American of inventions, the assembly line. Until then, marine chronometers had been made slowly, by hand. It was assumed that the fine tolerances needed for such precise performance were impossible to achieve (or maintain) with mass production.
Nevertheless, while Hamilton’s watchmakers and technicians were developing the chronometer, its engineers and production staff were adapting the factory’s equipment and assembly lines—and training Hamilton’s assembly line personnel—for the precision manufacturing needed to reproduce large numbers of marine chronometers. Whereas England and Switzerland together had made 300 to 400 per year, Hamilton expected to produce that amount monthly—”an amazing accomplishment,” says Rondeau. Hamilton proudly called its chronometers “a unique product of amazing precision,” but according to a 1943 company report, it considered its ability to mass-produce them its “greatest [wartime] achievement.”
American know-how. Hamilton’s prototypes passed the Navy’s tests, and the company was contracted to produce chronometers for every American vessel. “For years and years, the United States has been dependent upon European countries for our chronometers,” declared Capt. (later Commodore) Julius Frederick Hellweg, the superintendent of the U.S. Naval Observatory from 1930 to 1946. “Now, thanks to Hamilton, we have thrown off the yoke.”
(It’s worth noting that Elgin National Watch Co., then a major U.S. watchmaker, also had Navy contracts to create a marine chronometer. However, World War II ended without any Elgin chronometers being put into service.)
Hamilton’s production started slowly (number 60, now in Rondeau’s private collection, was delivered in early November 1942) but soon rose to 300-500 pieces per month, reaching a peak of 546 in October 1944, according to USNO’s Steve Dick. (During the same period, Hamilton reduced its price for the Marine chronometer from $625 to $390.)
By the time the war ended in mid-1945, the watch firm had delivered 10,902 of these magnificent timepieces, enough for “all the ships at sea,” as Rondeau put it. It was a feat “nothing short of a miracle,” said Capt. H.T. Chase of the Navy Bureau of Ships.
But it wasn’t only the Navy (which bought 8,902) that used them as master time sources. The Army Air Force bought 500, and the Maritime Commission bought 1,500. One was also given to President Franklin D. Roosevelt, who kept his in the White House map room “where we maintain a day and night watch,” he wrote. Hamilton continued making marine chronometers after the war, for a total of 13,984 by 1970, when it ended U.S. production.
“In effect, the Hamilton Watch Company transformed the production and maintenance of precision timekeepers from an arcane craft to a routine and was able to meet the demands of the Atlantic and Pacific Fleets of the U.S. Navy and the needs of the Allied merchant marine in both oceans,” wrote Dennis Chapman, an English historian specializing in technology, in a 1996 essay on military timepieces in the Horological Journal of the British Horological Institute. “This achievement, comparable to mass production of Liberty ships and the ubiquitous ‘Jeep,’ was a triumph of American ‘know-how’ and ‘can-do.’ “
Chronometers for all. Every U.S. vessel (and many belonging to U.S. allies) used a Hamilton chronometer for navigation. Battle-ships and aircraft carriers used Model 21, housed in a glass-covered wooden box, with its movement swung on brass gimbals to keep it level—and accurate—even in the roughest seas.
Model 22 (patented by Hamilton in the summer of 1942 and first produced in 1943) was used as an auxiliary timer on those big ships, and for navigation on most others (such as destroyers, submarines, merchant marine and hospital ships, tankers, and escort vessels). It was a chronometer watch (with a lever escapement), not a marine chronometer (which has a detent escapement). However, like the marine chronometer, it incorporated a number of innovations, including a 60-in.-long mainspring for steady power, and an innovative “safety setting.” (A pin had to be depressed to pull out the crown, making it impossible to accidentally pull up the crown and rotate the hands while winding it.) Though smaller and less delicate than Model 21, the Model 22 also was kept in a gimbaled wooden box.
Small vessels like PT boats used Hamilton’s Model 22 Deck Watch. It had the same 35-size movement as Model 22 but resembled an oversized pocket watch in a box. Another Hamilton creation, the Model 23 chronograph—or “navigational time and stop watch,” as Hamilton’s literature called it—was the first of its type made in America. It was issued to the air forces in both the United States and the United Kingdom.
‘A most reliable instrument.’ Hamilton chronometers were so essential to the war effort, they had their own 95-page Navy maintenance manual and received special care. Naval regulations prohibited moving a ship’s chronometer—its master time source—about the vessel. So, a “comparing [pocket] watch” (such as Hamilton’s Grade 2974B model) was used on deck and when the navigator took sightings on his sextant (after comparing his watch with the chronometer). A crewmember, usually the chief quartermaster, was charged with ensuring that the ship’s chronometer was wound every day and was properly maintained. He was also responsible for its safety, wrapping it and “putting it to bed” in case of battle and taking it with him if the crew had to abandon ship.
Watch historian Marvin Whitney wrote that Hamilton’s timekeeper “proved to be a rugged and most reliable instrument under some of the most severe conditions to which a timepiece was ever subjected. Hamilton’s chronometers survived, without ill effect, some of the greatest naval bombardments ever known to man.”
By war’s end in 1945, Hamilton timepieces ruled the seas, air, and land, getting victorious Allied troops to where they were going—on foot or by ship, plane, tank, submarine, or troop train—using (to cite its wartime logo) “Hamilton Time.” Says Rondeau: “It would have been impossible for the American military to achieve what it did in World War II without Hamilton.”
Many in the military services agreed. Henry H. Arnold, commanding general of the Army Air Force saluted Hamilton for “providing aircraft instruments [that] played such an important part in [the Allies’] completely successful victory.” Admiral Arleigh Burke said the U.S. battle fleets in the decisive Battle of Leyte Gulf, the largest naval battle in history, were “absolutely dependent” on Hamilton’s chronometers for “the accurate time essential to successful naval operations.”
Honored for excellence. The government realized that, too, and recognized the watch firm often for the quality, innovation, and quantity of its timekeeping products. In fact, Hamilton was the first watch firm to receive the Army-Navy “E” Flag and subsequent “E” stars for production excellence.
On June 14, 1945, Commodore Hellweg—the U.S. Naval Observatory superintendent himself—came to Pennsylvania to pay tribute to Hamilton’s officials and employees and to offer “the Navy’s deep appreciation and our congratulations.
“Your chronometers and watches have built up a reputation among men of the fighting fleet, whose safety depends on accurate time,” he told them.
“During the past two critical years,” he said, the U.S. Navy had “carried more Hamiltons than any other make in the world [and] Hamilton’s instruments vitally aided the prosecution of war. Without Hamilton’s wholehearted assistance, I don’t know what we would have done.”