David Prerau describes the international standardisation of time, according to Greenwich mean time, as the first artificial adjustment to natural sun time. This artificialisation of time is said to have been globally systematised via various technologies, including time balls, and the calculation of longitudinal and latitudinal grids. 

Due to the eccentricity of the earth’s orbit and the tilt of its axis, the time from one day’s local noon to the following day’s local noon can be somewhat more or less than twenty-four clock-hours, depending on the day of the year. For example, the time on an accurate clock can be ahead of the local sun time as shown on a sundial by as much as fourteen minutes in mid-February and can lag behind sun time by as much as sixteen minutes in early November. In fact, there are only four days of the year when the clock and the sun completely agree. The difference between sun time and clock time, called the equation of time, was originally calculated in about 1670 by John Flamsteed, Britain’s first royal astronomer.

Given the regularity of the clock and the irregularity of the observed sun, a perfectly accurate clock would have to be reset each day at noon. To avoid this, cities and towns began to set their clocks on the basis of mean time: the length of a meantime day is defined as the average length of all the days of the year. Mean time (or mean solar time) was the first artificial adjustment made to natural sun time.

Guns, bells, and time balls.

Mean time was first instituted in Geneva, Switzerland in 1780, and eventually most cities and towns followed suit. Even after mean local time was generally adopted, however, there was still the problem of keeping the population of a large city or region synchronized. Although more accurate clocks and watches were produced, as the nineteenth century progressed, they still could drift several minutes a day. Mean local time could be determined with the greatest precision by astronomical observatories that tracked clock stars, stars that appeared overhead each night at predictable times. In an effort to keep clocks and watches accurate, observatory time was often announced by firing a gun or ringing a bell each day at a designated hour or by dropping a time ball.

Time balls were large metal spheres that were dropped each day from a prominent building or tower at a precise time, often twelve noon. The exact time was relayed by telegraph from a nearby observatory. Time balls were first used to signal a precise time to ships at harbor, so each ship could set its chronometer accurately without having to send someone ashore. The Royal Greenwich Observatory began dropping a daily time ball as early as 1833. Soon a time ball was in use in many cities, so that at the designated hour observers at numerous vantage points could set their clocks to the accurate local observatory time. Thus the daily drop of the time ball fostered a uniform time for everyone in the area. A vestige of this practice is the illuminated ball dropped in New York City’s Times Square at exactly midnight each New Year’s Eve.

The use of mean local sun time and devices such as time balls allowed residents of each town or city to be synchronized, but there still was no coordination of times between different cities and regions. To understand how such a system might be possible, we need to consider that the relative sun times of two places is determined by their location on the globe. The ancient Greek astronomer, Hipparchus, was the first to imagine superimposing a grid on the earth’s surface; his grid consisted of 360 lines (corresponding to the degrees of a circle) connecting the North and South Poles at right angles to the equator, and 180 equally spaced lines circling the earth parallel to the equator. The lines running between the Poles indicated a location’s longitude, and the lines parallel to the equator indicated its latitude. The lines of longitude were later called meridians, from the Latin meridies (midday), because all places on the same meridian had local noon, when the sun is at its highest point, at the same time.

Latitude is measured north or south from the equator. For longitude, however, there is no obvious starting point. Therefore it is measured east or west from some designated line of longitude, and this is called the prime meridian. Up to the end of the nineteenth century, almost every major nation based its maps for land delineation and ship navigation upon its own defined prime meridian of longitude, usually the meridian through its capital city. Britain’s prime meridian went through London, Portugal’s through Lisbon, France’s through Paris, Russia’s through St. Petersburg, and the United States’ through Washington, D.C. To allow precise determination of longitude, the specific location of the prime meridian was usually located at an astronomical observatory in or near the capital city: the Royal Greenwich Observatory in Greenwich, England, just outside London; the Naval Observatory in Washington, D.C.; and the Pulkovo Observatory near St. Petersburg.

As the earth rotates, the sun appears to traverse fifteen degrees of longitude in one hour. Thus, each degree of longitude to the west, local noon occurs four minutes later. Consequently, any two cities not on the same meridian would have their clocks set at different times, depending on how many degrees their longitudes separate them. Even though each town determined its time independently, the worldwide system of local times worked quite effectively for several centuries. As long as travel and communications were relatively slow, it didn’t much matter that, for instance, in the United States when it was 12:00 noon in Chicago it was 12:31 in Pittsburgh, 12:24 in Cleveland, 12:17 in Toledo, 12:13 in Cincinnati, 12:09 in Louisville, 12:07 in Indianapolis, 11:50 in St. Louis, 11:48 in Dubuque, 11:39 in St. Paul, and 11:27 in Omaha. The relaxed pace of travel, the lack of instant communications, the inherent inaccuracy of contemporary clocks, and the less frantic pace of life all made minor time variations unimportant.

But then came the Industrial Revolution (Prerau 2005, 53-57).

Prerau, David. 2005. Seize the daylight: The curious and contentious story of daylight saving time. New York: Thunder’s Mouth Press.


When daylight saving time was proposed to Winston Churchill by William Willett, the policy was described by Churchill as representing another form of an artificial time under which humans already live. The distinction is made between all forms of artificial, humanly-conceived, time, and a real or natural temporality.

My right hon. Friend the Member for Mid-Norfolk, speaking early in the debate, said we should not begin lying in these matters. In these matters the country had begun lying a long time ago. When the local time, which varies in different parts of the country, was made a uniform time for the whole country, a great departure from the truth was undoubtedly made. You created a standard of artificial time, and we have long lived under that standard. Sidereal time is not solar time. Natural time is not solar time, solar time is not Greenwich time. Clock time never corresponds with the sun time, except on the meridian and on particular days in the year. National time is not local time, and when those who are in favour of this Bill are represented with departing from the true time, I am bound to say we may naturally ask not only what is truth but what is time? I venture to think that it is not very easy to discover ultimate sanction for any human or temporal arrangement. It is probable our arrangements about time have been fixed in the past mainly with regard to supposed convenience, and that they are conventional arrangements, to be governed by what we think is convenient for our general habits. Therefore, this Bill does not propose a change from natural time to artificial time, but only to substitute a convenient standard of artificial time for an inconvenient standard of artificial time (Churchill 1909, cc1777).

Churchill, Winston. 1909. “Daylight saving bill.” Hansard 1803-2005 – Commons sitting. New York: Thunder’s Mouth Press.


Vanessa Ogle reports how in 1905, the Indian government sought to introduce a national, standard time, to engender geopolitical cohesion with other countries. Whilst a politically popular decision, Ogle notes that the media, and the Indian population, criticised such a change. The basis of this criticism was that the government had created an artificial, fictitious time, which had separated Indians from their natural, solar time.

In the face of what appeared to be a solid consensus among those canvassed, the Government of India moved to introduce the time five hours and 30 minutes ahead of Greenwich to the colony. The new time was designated as “Indian Standard Time,” to deflect from its potentially controversial “British” source…

In January 1905, the Government of India instructed the Public Works Department to introduce the time five hours and thirty minutes in advance of Greenwich as “Indian Standard Time” while in Burma the time to be adopted would run six hours and thirty minutes fast. As of July 1, 1905, all railways and telegraphs on the Indian subcontinent were to follow the new time…

The Government of India accurately anticipated the opposition to uniform time it was about to unleash, although perhaps less so its scope and intensity. Once more, it was Bombay, and to a lesser extent Calcutta, that became the focal point of collisions between deeply rooted urban identities and imperial policies. In 1905 as compared with 1881, protests against a new colony- wide mean time struck a much more anti- British chord than previously. Now it mattered that this was a time decreed by the British colonizers, that it was “British” time being imposed on colonial subjects. Twenty years after the Government of India’s first brush with time, under the changed circumstances of British rule in India in 1905, retaining local time became a matter of Indian national politics. Indians now perceived the change in official mean times as yet another in a long series of attempts by the colonial state to meddle with local and personal affairs…

Such was the situation when Indian Standard Time was to be introduced in the summer of 1905 on railways and telegraphs. Emboldened perhaps by similar moves of other local administrations, Bombay authorities suddenly made the decision to push for the adoption of Indian Standard Time for all official purposes and in government offices throughout the Bombay Presidency. In October 1905, the Government of Bombay asked the Government of India for permission to introduce the new time.

Outside the meeting halls of the Bombay Municipal Corporation, the general public was voicing its dislike for the new order of time evermore loudly. As with other time changes in Europe and North America, the new Indian mean time was criticized for being “artificial” and unnatural. “We are asked to forget our natural time, the same that we have been familiar with from times immemorial, and adopt the new ‘standard’ which the ingenuity of the Astronomer Royal has devised,” the newspaper Kaiser-i-Hind complained, adding that nature herself must be in rebellion against this time. Later, the paper proclaimed, “nobody has asked for artificial time” to replace a time “which Nature has given to us and which mankind has faithfully followed these eight thousand years at least.” A letter to the editors of the Bombay Gazette found the new time to be “fictitious.” Another newspaper established, “the solar time is really the true time which regulates the affairs of each Indian house hold” (Ogle 2015, 107-12).

Ogle, Vanessa. 2015. The global transformation of time (1870 – 1950). Cambridge and London: Harvard University Press.