Search results
Results from the WOW.Com Content Network
c. 3500 BC - Egyptian obelisks are among the earliest shadow clocks. [1] c. 1500 BC - The oldest of all known sundials, dating back to the 19th Dynasty. [2] c. 500 BC - A shadow clock is developed similar in shape to a bent T-square. [3] 3rd century BC - Berossos invents the hemispherical sundial. [4] 270 BCE - Ctesibius builds a water clock.
The equation of time was engraved on sundials so that clocks could be set using the Sun. In 1720, Joseph Williamson claimed to have invented a clock that showed solar time, fitted with a cam and differential gearing, so that the clock indicated true solar time. [137] [138] [139]
The categorisation of the past into discrete, quantified named blocks of time is called periodization. [1] This is a list of such named time periods as defined in various fields of study. These can be divided broadly into prehistorical periods and historical periods (when written records began to be kept).
Timeline of railway history (428 BCE–present) Timeline of United States railway history (1810s–present) Timeline of the London Underground (1820s–present) Timeline of motorized bicycle history (1868–1986) Timeline of aviation (1700/1000 BCE–present) Timeline of rocket and missile technology (1st century–2010) Timeline of spaceflight
Timelines of world history; List of timelines; Chronology; See calendar and list of calendars for other groupings of years. See history, history by period, and periodization for different organizations of historical events. For earlier time periods, see Timeline of the Big Bang, Geologic time scale, Timeline of evolution, and Logarithmic timeline.
The date used as the end of the ancient era is arbitrary. The transition period from Classical Antiquity to the Early Middle Ages is known as Late Antiquity.Late Antiquity is a periodization used by historians to describe the transitional centuries from Classical Antiquity to the Middle Ages, in both mainland Europe and the Mediterranean world: generally from the end of the Roman Empire's ...
The geologic time scale is a way of representing deep time based on events that have occurred throughout Earth's history, a time span of about 4.54 ± 0.05 Ga (4.54 billion years). [3] It chronologically organises strata, and subsequently time, by observing fundamental changes in stratigraphy that correspond to major geological or ...
In Estonian, "e.m.a." (enne meie ajaarvamist, before our time reckoning) and "m.a.j." (meie ajaarvamise järgi, according to our time reckoning) are used as BCE and CE, respectively. Also in use are terms "eKr" (enne Kristust, before Christ) and "pKr" (pärast Kristust, after Christ). In all cases, the abbreviation is written after the year number.