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A day is either the interval of time during which the sun is continuously above the horizon, or the time occupied by a revolution of the earth on its axis, embracing this interval (the period of light) as well as the interval of darkness. The day in the latter sense may be measured in more than one way. If we measure it by the apparent movement of the stars, caused by the rotation of the earth on its axis, we must call day the period between the time when a star is on the meridian and when it again returns to the meridian: this is a sidereal day. It is uniformly equal to 23 hours, 56 minutes, 4.098 seconds. But more important than this is the solar day, or the interval between two passages of the sun across the meridian of any place. The latter is about 4 minutes longer than the former, owing to the revolution of the earth round the sun, and it is not of uniform length, owing to the varying speed at which the earth moves in its orbit and to the obliquity of the ecliptic. For convenience an average of the solar day is taken, and this gives us the mean solar or civil day of 24 hours, the difference between which the actual solar day at any time is the equation of time.
The length of the days and nights at any place varies with the latitude and season of the year, owing to the inclination of the earth's axis. In the first place, the days and nights are equal (twelve hours each) all over the world on the 21st of March and the 21st of September, which dates are called the vernal (spring) and autumnal equinoxes. Again, the days and nights are always of equal length at the equator, which, for this reason, is sometimes called the equinoctial line. With these exceptions, we find the difference between the duration of the day and the night varying more and more as we recede from the equator, and at the poles the year consists of one day of six months' duration, and one night of the same.
The Babylonians began the day at sun-rising; theJews at sun-setting; the Egyptians and Romans at midnight, as do most modern peoples. The civil day in most countries is divided into two portions of twelve hours each. The abbreviations PM. and AM. (the first signifying post meridiem, Latin for afternoon; the latter ante meridiem, forenoon) are requisite, in consequence of this division of the day. The Italians in some places reckon the day from sunset to sunset, and enumerate the hours up to twenty-four; the Chinese divide it into twelve parts of two hours each.
For astronomical purposes the day is divided into twenty-four hours instead of two parts of twelve hours. Formerly it began at noon, but since the 1st of January 1885, the day of twenty-four hours begins at midnight at Greenwich Observatory; and this reckoning is now generally adopted for astronomical purposes elsewhere than at Greenwich. The Greenwich day practically determines the date for all the world. At mid-day at Greenwich the date (day of the week and month) is everywhere the same, though there are all possible differences in naming the hour of the day. But mid-day at Greenwich is the only instant at which we ever have the same date all over the world. The meridian of midnight, which is then at 180 degrees east or west, goes on revolving, gradually bringing a new date to every place to the west of that line, but obviously not bringing that new date to the places immediately to the east of that line until twenty-four hours after. From this it follows that whereas places on the one side of the globe never have a different date except when midnight lies between them, places on the opposite side of the globe, and on different sides of the meridian of 180 degrees east Or west never have the same date except when midnight lies between them. The actual difference of time between Wellington in New Zealand and Honolulu in Hawaii is only about two hours; yet a person at Wellington may date a letter 9 o'clock AM 26th June, while another writing at the same instant at Honolulu dates his 11 o'clock AM 25th June.
James Donaldson was a Scottish scholar. He was born in 1831, at Aberdeen and died after 1906. He was educated at Aberdeen and also at Manchester New College, London, and Berlin University. After being rector of Stirling High School, a classical master and rector of Edinburgh High School, he was appointed in 1881 to the Chair of Humanity (Latin) in Aberdeen University. In 1886 he became principal of the United College of St. Salvator and St. Leonard in St. Andrew's University, and in 1890 principal of the university. He published a Modern Greek Grammar for the
use of Classical Students (1853); Lyra Graeca: Specimens of Greek Lyric Poets, with Introduction and Notes (1854); History of Christian Literature and Doctrine from the Death of the Apostles to the Nicene Council (1861-1866); The Ante-Nicene Christian Library (24 volumes 1867-1872, edited jointly with Professor A. Roberts); The Apostolical Fathers (1874); Lectures on the History of Education in Prussia and England (1874); The Westminster Confession of Faith (1905); and other works, besides articles in the Encyclopaedia Britannica.
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Ante-date is a business term to date a document before the date on which it is drawn up. This is not necessarily illegal or improper. For instance, an
ante-dated cheque is not in law invalid.
Research Ante-Date
King Henry V is a play written by Shakespeare. It is set in England and France. It opens with a chorus and then in an ante-chamber in the King's palace in London.
Research King Henry V
King Henry VIII is a play written by Shakespeare. It is set chiefly in London and Westminster; once at Kimbolton. It opens following a prologue in an ante-chamber in the palace in London.
King Henry VIII is the title character in the play.
Research King Henry VIII
The Winter's Tale is a play written by Shakespeare. It is set sometimes in Sicilia and sometimes in Bohemia. It opens in an ante-chamber in Leontes' palace in Sicilia whereupon enter camillo and archidamus.
Research The Winter's Tale
AAC is an abbreviation for Alaskan Air Command
AAC is an abbreviation for Aeronautical Advisory Council
AAC is an abbreviation for Agricultural Advisory Council
AAC is an abbreviation for Amateur Athletic Club
AAC is an abbreviation for Anno Ante Christum
AAC is an abbreviation for Army Air Corps
AAC is an abbreviation for Adaptive Antenna Control
AAC is an abbreviation for Alaskan Air Command
AAC is an abbreviation for Automatic Amplitude Control
AAC is an abbreviation for Advanced Audio Coding
Research AAC
A is an abbreviation for Acting
A is an abbreviation for effective aperture area of antenna
A is an abbreviation for Academician
A is an abbreviation for Academy
A is an abbreviation for Accepted
A is an abbreviation for Active
A is an abbreviation for Adjective
A is an abbreviation for Adult
A is an abbreviation for Aftermath
A is an abbreviation for Advanced
A is an abbreviation for Ampere
A is an abbreviation for Analog
A is an abbreviation for Ante
A is an abbreviation for Angstrom
A is an abbreviation for Area
A is an abbreviation for Argon
A is an abbreviation for Associate
A is an abbreviation for Atomic
A is an abbreviation for Acre
A is an abbreviation for America
A is an abbreviation for Amateur
A is an abbreviation for Answer
A was formerly an abbreviation for Argon
AC is an abbreviation for Alternating Current
AC is an abbreviaton for Armoured Cable
AC is an abbreviaton for Asbestos Cement
AC is an abbreviation for Air-Conditioned
AC is an abbreviation for Air Conditioning
AC is an abbreviation for Ante Christum
AC is an abbreviation for Ante Cibum
Ac is an abbreviation for Actinium
AC is an abbreviation for Aircraft
AC is an abbreviation for Area Code
AC is an abbreviation for Athletic Club
AC is an abbreviation for Appeal Court
AC is an abbreviation for Army Council
AC is an abbreviation for Ambulance Corps
AC is an abbreviation for Aircraftsman
AC is an abbreviation for Agricultural College
AC is an abbreviation for Arts Council
AC is an abbreviation for Assistant Commissioner
AC is an abbreviation for Appeal Cases
AC is an abbreviation for Companion of the Order of Australia
AC is an abbreviation for Appellation Controlee
AC is an abbreviation for Aircraftman
AC is an abbreviation for Hydrogen Cyanide
ac is an abbreviation for Author's correction
Research AC
AM is an abbreviation for Armenia
AM is an abbreviation for Amplitude Modulation
AM is an abbreviation for Ante Meridiem
AM is an abbreviation for Artium Magister
Am is an abbreviation for Americium
AM is an abbreviation for Associate Member
AM is an abbreviation for Albert Medal
AM is an abbreviation for Master of Arts
AM is an abbreviation for Member of the Order of Australia
AM is an abbreviation for Air Mail
AM is an abbreviation for Air Medal
AM is an abbreviation for Airlock Module
AM is an abbreviation for Antenna Module
AM is an abbreviation for Arithmetic Mean
AM is an abbreviation for Application Master
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The Probert Encyclopaedia was designed, edited and programed by
Matt and Leela Probert
©1993 - 2009 The Probert Encyclopaedia
Southampton, United Kingdom
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