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The invention of the candle clock was attributed by the Anglo-Saxons to Alfred the Great, king of Wessex (r. 871–889), who used six candles marked at intervals of one inch (25 mm), each made from 12 pennyweights of wax, and made to be 12 centimetres (4.7 in) in height and of a uniform thickness.
The repeating clock was invented by the English cleric and inventor, the Reverend Edward Barlow in 1676. [2]: 206 His innovation was the rack and snail striking mechanism, which could be made to repeat easily and became the standard mechanism used in both clock and watch repeaters ever since. The best kind of repeating clocks were expensive to ...
Here, the graduated candle supplied a means of determining time at night. Similar candles were used in Japan until the early 10th century. You Jiangu's device consisted of six candles made from 72 pennyweights (24 grains each), of wax, each being 12 inches high, of uniform thickness, and divided into 12 sections each of one inch.
18th Century oil-lamp clock. Oil-lamp clocks are clocks consisting of a graduated glass reservoir to hold oil - usually whale oil, which burned cleanly and evenly - supplying the fuel for a built-in lamp. As the level in the reservoir dropped, it provided a rough measure of the passage of time.
A torsion pendulum clock, more commonly known as an anniversary clock or 400-day clock, is a mechanical clock which keeps time with a mechanism called a torsion pendulum. This is a weighted disk or wheel, often a decorative wheel with three or four chrome balls on ornate spokes, suspended by a thin wire or ribbon called a torsion spring (also ...
Type 'C' Form 'A' twin detector crystal radio set, manufactured by British Thomson Houston Ltd. in 1924, kept at the Museum of the radio - Monteceneri (Switzerland) Early radio telegraphy used spark gap and arc transmitters as well as high-frequency alternators running at radio frequencies. The coherer was the first means of detecting a radio ...
With gas lighting, theatres would no longer need to have people tending to candles during a performance, or having to light each candle individually. "It was easier to light a row of gas jets than a greater quantity of candles high in the air." [37] Theatres also no longer needed to worry about wax dripping on the actors during a show.
Early clock dials did not indicate minutes and seconds. A clock with a dial indicating minutes was illustrated in a 1475 manuscript by Paulus Almanus, [48] and some 15th-century clocks in Germany indicated minutes and seconds. [49] An early record of a seconds hand on a clock dates back to about 1560 on a clock now in the Fremersdorf collection.