By Jonny Lupsha, News Writer

The New Year’s countdown at Times Square has its roots in English ship clock calibration, BBC News reported. First debuted in Portsmouth in 1829, the ball would be lowered from a high pole at precisely 1:00 p.m. Measuring time is an intriguing scientific activity.

According to the BBC News article, British Royal Navy officer Robert Wauchope invented the “time ball” to ensure that mariners had their clocks precisely set to the proper time in order to sail safely with the tides. “Typically, at 12:55, a creaky piece of machinery would raise a large painted orb halfway to the top of a pole or flagstaff; at 12:58, it would proceed to the top; and precisely at 13:00, a worker would release it to drop down the pole,” the article said. This let the ships’ masters calibrate their ships’ timepieces without them having to come ashore and visit an observatory. So how do we physically measure and mete out time?

Sundials

Sundials are one of humanity’s earliest scientific efforts at measuring the time of day. “You can always put a stick [in the ground] exactly vertically, but then what you would realize is that if that stick stayed there all year long, the time of day that it was measuring would be different in springtime, in summer, in fall, and in winter,” said Dr. Sean Carroll, Senior Research Associate in Physics at the California Institute of Technology.

“Eventually, [people] realized that if you aligned the stick with the axis of the Earth’s rotation, the sundial would tell accurate time. It would tell you the same hour of the day whether you were in winter, spring, summer, or fall.”

Of course, sundials don’t work at all at night or on cloudy or rainy days. They can be buried entirely in snowfall and they are neither portable nor precise. Galileo invented a steadily rocking pendulum that kept accurate time, but as seafaring increased, the world needed something more stable and dependable than the pendulum and more portable and precise than a sundial.

A 150-Year Journey, by My Watch

As trade routes opened and sailors spent time at sea, measuring your location by the stars depended on knowing what time it was, since the stars move in the sky based on the Earth’s rotation. Timekeeping was crucial.

“This puzzle was so important that the British parliament offered a prize of 20,000 British pounds if someone could figure out how to measure time accurately even at sea,” Dr. Carroll said. “20,000 British pounds at the time corresponds to $4.5 million today.”

Pendulums were out due to the rocking of ships. Spring-loaded timepieces lost accuracy at different locations due to varying temperature and humidity making the metals in the springs expand and contract and then fail to unwind evenly.

“The problem was ultimately solved in the year 1761 by an inventor named John Harrison who invented the Marine Chronometer,” Dr. Carroll said. “His ultimate, prize-winning chronometer was only about five inches across. Harrison did things like building his springs out of strips of metal that were different kinds of metal on different sides, so as one expanded in the temperature or the pressure, the other one would contract, and they would cancel out.”

According to Dr. Carroll, Harrison’s chronometer told time to within 1/10th of a second per day, winning him the 20,000 British pounds. Robert Wauchope’s time ball came along just 50 years later. Meanwhile, pocket watches were popularized in the 19th century; although, wristwatches were snubbed as classless and low-brow. It wasn’t until World War I, nearly 150 years after Harrison’s chronometer was invented, that wristwatches came into their own. They offered soldiers the means to keep both hands free to carry their weapons while being able to check the time with a flick of the wrist.

Dr. Sean Carroll contributed to this article. Dr. Carroll is a Senior Research Associate in Physics at the California Institute of Technology. He earned his undergraduate degree from Villanova University and his Ph.D. in Astrophysics from Harvard in 1993.