Keep time in style with this traditional tabletop clock, a great way to round out a decorative vignette while adding essential function. Crafted from wood and metal, this circular design sits atop a curved base and pairs an antique dial with a deep red finish. The glass-inlaid clock face sports glow-in-the-dark hands, so you can check the time in the wee hours and early evening, while a quartz movement keeps this design tickin’ and tockin’. Requires a battery.
The most accurate mechanical timekeeper is the Shortt pendulum clock; it makes use of the movement described above for electric master clock systems. The Shortt pendulum clock consists of two separate clocks, one of which synchronizes the other. The timekeeping element is a pendulum that swings freely, except that once every half minute it receives an impulse from a gently falling lever. This lever is released by an electrical signal transmitted from its slave clock. After the impulse has been sent, a synchronizing signal is transmitted back to the slave clock that ensures that the impulse to the free pendulum will be released exactly a half minute later than the previous impulse. The pendulum swings in a sealed box in which the air is kept at a constant, low pressure. Shortt clocks in observatories are kept in a room, usually a basement, where the temperature remains nearly constant, and under these conditions they can maintain the correct time to within a few thousandths of a second per day.
A. Like many items today, the amount you’ll pay for an alarm clock depends on how much technology you want layered onto it. If you desire nothing but a simple analog alarm clock that rouses you with a single tone, you could spend as little as $10. A slightly more sophisticated clock radio might cost $20 or so. If you want a deluxe digital alarm clock with screen projection, Bluetooth capability, MP3 player, or other cool features, you’re looking at a price of anywhere from $40 to $90.
This 32-1/2" large wall clock's dial is aged with black Arabic numerals, and features an antique pendulum visible through peep hole. Aged black minute and hour hands with a red second hand complete the look. Lightly distressed finish in Hampton Cherry make this with glass crystal. A handsome large wall clocks with pendulum. Quartz, battery operated movement. One Year Warranty.
An alarm clock (alarm for short) is a clock that is designed to alert an individual or group of individuals at specified time. The primary function of these clocks is to awaken people from their night's sleep or short naps; they are sometimes used for other reminders as well. Most use sound; some use light or vibration. Some have sensors to identify when a person is in a light stage of sleep, in order to avoid waking someone who is deeply asleep, which causes tiredness, even if the person has had adequate sleep. To stop the sound or light, a button or handle on the clock is pressed; most clocks automatically stop the alarm if left unattended long enough. A classic analog alarm clock has an extra hand or inset dial that is used to specify the time at which to activate the alarm. Alarm clocks are also found on mobile phones, watches, and computers.
late 14c., clokke, originally "clock with bells," probably from Middle Dutch clocke (Dutch klok) "a clock," from Old North French cloque (Old French cloke, Modern French cloche), from Medieval Latin (7c.) clocca "bell," probably from Celtic (cf. Old Irish clocc, Welsh cloch, Manx clagg "a bell") and spread by Irish missionaries (unless the Celtic words are from Latin); ultimately of imitative origin.
For some scientific work timing of the utmost accuracy is essential. It is also necessary to have a standard of the maximum accuracy against which working clocks can be calibrated. An ideal clock would give the time to unlimited accuracy, but this is not realisable. Many physical processes, in particular including some transitions between atomic energy levels, occur at exceedingly stable frequency; counting cycles of such a process can give a very accurate and consistent time—clocks which work this way are usually called atomic clocks. Such clocks are typically large, very expensive, require a controlled environment, and are far more accurate than required for most purposes; they are typically used in a standards laboratory.
Small in size but striking in style, this eye-catching wall clock brings a dash of contemporary flair to any arrangement in your home. Showcasing a sunburst silhouette measuring 20" in diameter, this round silver-finished design is crafted with an iron and mirrored frame comprised of black spokes with orb-like accents. A petite glass clock face with sword-style hands sits in the center, allowing you to keep an eye on the hour in any room.
This curvaceous wall clock features carved accents and a turned urn finial which complement the unique style. The aged dial offers black Roman numerals and decorative black hands. A special 80th Anniversary Edition. The wooden stick swinging pendulum features an antique-brass spun bob. Finished in Tuscany Cherry on select hardwoods and veneers. Quartz, dual chime movement plays switchable quarter hour 4/4 Westminster or Ave Maria chimes. Volume control and automatic nighttime chime shut-off option.
Seriously, projection clocks are awesome. Apart from the obvious design perks, you get high-speed USB charging for your phone or tablet overnight. (By the way, we recommend setting multiple alarms no matter what clock you buy, you heavy sleeper, you.) The large LED display of Electrohome EAAC475 is sure to wake you up if the reflection of the projection and the sound doesn’t. You can set this up without worry—power failure doesn’t stand a chance. The lithium-ion battery that’s included in this model acts as a backup power reserve, so you’re never caught with your guard down.
This isn’t for just any old sleeper. This is going to ensure that you get up with every bit of vigor in its little electronic body. Sonic Alert brings us a seriously powerful alarm clock that actually shakes the bed to get you out of it, and comes with a large red LCD screen. You’ll have red flashing in your eyes, the bed rumbling, and a loud sound as the light pulsates to get you up. The world isn’t ending, you’re just getting up for work again. Look alive, tiger!
Any expansion or contraction of the rod caused by changes of temperature will affect the timekeeping of a pendulum; e.g., a pendulum clock with a steel rod will lose one second a day for a rise in temperature of approximately 4 °F (2.2 °C). For accurate timekeeping, the length of the pendulum must be kept as nearly constant as possible. This may be done in several ways, some of which use the differing coefficients of expansion (the amount of expansion per degree change in temperature) of different metals to obtain a cancelling-out effect. In one popular compensation method, the bob consists of a glass or metal jar containing a suitable amount of mercury. The gridiron pendulum employs rods of different metal, usually brass and steel, while in the zinc-iron tube the pendulum rod is made of concentric tubes of zinc and iron. An improved method, however, is to make the pendulum rod from a special alloy called Invar. This material has such a small coefficient of expansion that small changes of temperature have a negligible effect and can easily be compensated for if required.
As stylish as it is functional, this lovely clock lends a touch of charm and classic appeal to your tabletop display. A traditional design, it showcases a rounded frame with a pedestal base and a solid black finish. The neutral-toned clock face is accented with black Roman numeral numbering and three thin black hands. Crafted from plastic, it is a budget-friendly choice. It also features a beeping alarm for added convenience.
Stay punctual with an alarm clock! They are great for waking you up in the morning or simply reminding you of special events. These items are a household must-have! Perfect for bedside nightstands, most alarm clocks feature a built-in FM radio to enjoy your favorite radio station, as well as a snooze button for when you need 5 to 10 minutes more sleep. iHome? clock radios have dock for MP3 players to listen to music through the speakers. Choose from a variety of unique, creative designs that are great for virtually any d‚cor.