Strong, durable, super large time display makes the model perfect for those who either want a big number clock, or for visually impaired individuals who need extra-large numerals, The red LED display on a black background, makes the contrast ideal for easy viewing. The electric power with battery backup lets you sleep with peace of mind and the extra-large snooze bar keeps nap-time within reach. This clock is a solid purchase.
A major stimulus to improving the accuracy and reliability of clocks was the importance of precise time-keeping for navigation. The position of a ship at sea could be determined with reasonable accuracy if a navigator could refer to a clock that lost or gained less than about 10 seconds per day. This clock could not contain a pendulum, which would be virtually useless on a rocking ship. In 1714, the British government offered large financial rewards to the value of 20,000 pounds, for anyone who could determine longitude accurately. John Harrison, who dedicated his life to improving the accuracy of his clocks, later received considerable sums under the Longitude Act.
The Howard Miller Postema Oversized 49" Wall Clock is a unique piece that will remind you of oversized clocks. This round-shaped clock is a piece of style with the traditional accents. The clock has an espresso finish and round shape. You can mount this clock in any room at your home. This clock can also be placed in big halls or entryways because of its size and functionality. The clock has a distressed finish that complements the espresso varnish. This antique wall clock is made from wrought...
The pendulum is a reliable time measurer because, for small arcs, the time required for a complete swing (period) depends only on the length of the pendulum and is almost independent of the extent of the arc. The length of a pendulum with a period of one second is about 39 inches (990 mm), and an increase in length of 0.001 inch (0.025 mm) will make the clock lose about one second per day. Altering the length of a pendulum is therefore a sensitive means of regulation. The alteration is usually carried out by allowing the bob to rest upon a nut that can be screwed up or down the pendulum rod.
Can we let you in on a secret? From pocket watches to grandfather clocks, a timepiece often tells as much about its owner as it does the hour. With a piece like this, you can ensure that it makes a statement in rustic-inspired style. Crafted from solid rubberwood with black metal spade handles, this piece is full of cottage charm. Featuring a distressed finish and roman numerals alongside its open back, this piece is sure to make welcome guests to your home with its modern farmhouse details.
The timekeeping element of a quartz clock consists of a ring of quartz about 2.5 inches (63.5 mm) in diameter, suspended by threads and enclosed in a heat-insulated chamber. Electrodes are attached to the surfaces of the ring and connected to an electrical circuit in such a manner as to sustain oscillations. Since the frequency of vibration, 100,000-hertz, is too high for convenient time measurement, it is reduced by a process known as frequency division or demultiplication and applied to a synchronous motor connected to a clock dial through mechanical gearing. If a 100,000 hertz frequency, for example, is subjected to a combined electrical and mechanical gearing reduction of 6,000,000 to 1, then the second hand of the synchronous clock will make exactly one rotation in 60 seconds. The vibrations are so regular that the maximum error of an observatory quartz-crystal clock is only a few ten-thousandths of a second per day, equivalent to an error of one second every 10 years.
This 24" large metal Large Wall Clock is finished in a dark rubbed bronze with aged bronze accents at the 3, 6, 9 and 12 positions. The aged dial features a subtle center pattern, aged black Roman numerals, black spade hour and minute hands and a convex glass crystal. A twisted metal ring frames the dial. Quartz, battery operated movement. One year warranty and Free Shipping.
In China, a striking clock was devised by the Buddhist monk and inventor Yi Xing (683–727). The Chinese engineers Zhang Sixun and Su Song integrated striking clock mechanisms in astronomical clocks in the 10th and 11th centuries, respectively. A striking clock outside of China was the water-powered clock tower near the Umayyad Mosque in Damascus, Syria, which struck once every hour. It was constructed by the Arab engineer al-Kaysarani in 1154. In 1235, an early monumental water-powered alarm clock that "announced the appointed hours of prayer and the time both by day and by night" was completed in the entrance hall of the Mustansiriya Madrasah in Baghdad.
“I am the heaviest sleeper and was setting four or five alarms on my phone to wake me up. After being late a few times, I decided to purchase this alarm clock to help me wake up on time. I couldn’t be happier with my purchase. … The bed shaker is super important. I put it under my pillow, and it shook me awake; the loud beep helped too. If you can sleep through earthquakes and shouting family members, this is the alarm clock for you.”