|
5 October 2023 — Dropping the Ball: One Simple Invention in the Complex Evolution of Marine Navigation
One month from today, Daylight Saving Time in the US will end. If you’re like me, you’ll carry your phone from one room to the next, resetting the time on the kitchen range, the alarm clock, the car… everywhere we find a clock. I use my phone because cell phones regularly verify that information from time servers connected to their networks. Those of us over a certain age can remember a time when you still used a phone to check the time, but you had to actually dial a local number, and a friendly-but-authoritative voice would announce the correct time, or the time and weather, at fixed intervals.
Setting a clock today—ensuring that the clock agrees with a remote clock somewhere else—is often a minor household adjustment: setting the time on a new device, banishing the flashing digital clock display after a power disruption, or “falling back” for the end of Daylight Saving Time. But in the development of ocean navigation, a clock’s accuracy was crucial. A ship’s longitude could be determined by measuring the position of a celestial body and using published tables, provided one knew the exact local time and the current time at a different set location, such as the port of Greenwich. This process was revolutionized by the development of a clock designed to be accurate aboard ship, overcoming the challenges once enumerated by Sir Isaac Newton: “the motion of the ship, the variation of heat and cold, wet and dry, and the difference of gravity in different latitudes.” The man credited with that monumental invention was John Harrison, a Yorkshire-born craftsman who devoted decades of his life to perfecting a clock that could keep accurate time aboard ship. He presented his first iteration of the device to the UK’s Board of Commissioners for the Discovery of Longitude at Sea in 1736, and was rewarded with a portion of the £20,000 (about £4 million today, or $4.8 million!) prize promised to the person who could come forward with a practical solution to determining longitude at sea; the Board wasn't yet convinced that Harrison's timepiece was the solution they sought to reward. Harrison continued to perfect his invention, in the face of opposition from theorists advocating for other navigational methods; as he presented the Board with the improved models, he received additional portions of the prize money. He didn't see the final payment, which brought his total over the promised £20,000, until 1773.
|  | John Harrison, whose timepiece kept accurate time, even under the the challenges of shipboard conditions. Image: PD | |
Despite their virtues, even excellent marine chronometers had to be checked regularly for accuracy, because even a few seconds’ deviation could throw off calculations considerably. When in port, captains would bring their chronometers to a qualified horologist for calibration and to address any more serious issues. But thinkers of the age were always looking for other ways to confirm the time. Probably the most entertaining to our modern understanding (but an assault on the heartstrings of animal lovers everywhere) was the theory involving “sympathetic powder.” The mystical powder was said to have the power to connect a wounded being with objects related to its wound; an anonymously-published booklet suggested that a dog be stabbed before being sent on a sea voyage, and its used bandages be kept with a business associate in port. Those bandages would then be dipped in the powder at an agreed-upon time—for example noon, in London. The powder would simultaneously cause pain to the dog; a navigator with the dog present at sea would know from the animal’s yelp of discomfort that it was exactly noon in London. Scholars aren’t in agreement over whether the pamphlet, published anonymously, was a piece of contemporary satire, but it is a story that frequently pops up in discussion of the struggle to accurately measure longitude.
While ships were in sight of land near a major port, at least, they had a less mystical option. In 1829 the first known time ball of the modern era was installed in Portsmouth, England, after such a project was proposed by Captain Robert Wauchope, RN, in a letter to the British Admiralty in December of 1824. The ball was mounted on a pole on top of a building so as to be visible by ships in the harbor. The ball was raised to the top of the pole, and at precisely 1 PM it was lowered again. The experiment was so well-regarded that a time ball was installed atop the Royal Observatory (wherein astronomers determined the time from celestial observation). The second the bright red ball began its descent, observers checked their chronometers for agreement.
|
 | |
Notice to Mariners, Admiralty, 28 October 1833
The Lords Commissioners of the Admiralty hereby give notice, that a ball will henceforth be dropped, every day, from the top of a pole on the Eastern Turret of the Royal Observatory at Greenwich, at the moment of one o’clock P. M. mean solar time. By observing the first instant of its downward movement all vessels in the adjacent reaches of the river as well as in most of the docks, will thereby have an opportunity of regulating and rating their chronometers.
The ball will be hoisted half-way up the pole, at five minutes before One o’clock, as a preparatory signal, and close up at two minutes before One.
By command of their Lordships
John Barrow
Photo: Rept0n1xvia Wikimedia Commons
| That time ball in Greenwich, which is still in use today, was followed in 1834 by one installed on the island of St. Helena, and subsequently in ports scattered around the world; an Admiralty list of time balls intended for mariners (not including inland municipal time balls) in 1898 numbered 94. Interestingly, time balls in the UK fall at 1 PM; the practice in the US is to drop them at noon. The ball-drop was a manual operation initially, but as electricity began to be introduced into our technologies, the system evolved of a “master” clock that would send out electrical impulses to “sympathetic” clocks, and the electrical impulse was used to trigger a mechanism that raised and subsequently dropped the ball. The Greenwich time ball was automated thus in 1852. |
|
The US Naval Observatory was the first location of a maritime time ball in the United States, in 1845. Photo: Wikimedia Commons | |
You can’t please all of the people all of the time, though. One individual who disapproved of the popularity of time balls was Frank Waldo of Cincinnati. In a letter to the editor of Science magazine in 1890, he expressed his concern that the prevalence of time balls had drastically reduced the frequency with which captains took their marine chronometers to be inspected by a professional, thus increasing the likelihood they would not be alerted when their instruments needed maintenance or repair. Waldo advocated for a scheme of frequent mandatory inspections of navigational timepieces. | |
The most famous time ball today is, of course, the ball dropped above Times Square in New York City to mark the first seconds of the new year. Unlike maritime time balls, which signal the time at the beginning of their descent, the New Year's Eve ball marks the stroke of midnight at the end of its fall. Photo: Anthony Quintano via Wikimedia Commons | |
|
Today, of course, the accurate time is projected at us from our phones, our computers, cable news channels, and many of our more networked appliances. Satellite-enabled navigation systems give us almost-frighteningly accurate location data. It’s good to take a step back and recognize the intense struggle it was to develop the tools of navigation that saved countless lives by helping keep ships on course, and things as simple—and yet so important—as a bright red ball that demanded agreement on the exact time, once every 24 hours.
Extra Credit
Classic telephone time service recordings at Telephoneworld.org
Longitude [The tv-movie adaptation]
Sea History Today is written by Shelley Reid, NMHS senior staff writer. Past issues can be read online by clicking here.
| | | | |
