How old is the day of 24 equal hours?
According to Wikipedia, concepts superficially similar to the modern system of hours have been around since at least ancient Egypt c. 2800 BC. But their system divided "daytime" (after dawn and before sunset) and "nighttime" (after sunset and before dawn) into 12 hours each, whose length would of course vary at different times of the year.
At some point in the intervening ~5000 years, we moved to a system of a day being composed of 24 equal hours that daytime or nighttime could take up a varying quantity of at different times during the year. But I'm having trouble determining at what point this concept first took hold.
There's a related question on here that was closed for being confusing and unclear what exactly was being asked, so to avoid the same fate, here's exactly what I'm asking: when (and by who) was the system established in which each day has 24 hours, each of which are supposed to be of identical length rather than being dependent on varying values such as the length of time that the sun is in the sky?
time-keeping
add a comment |
According to Wikipedia, concepts superficially similar to the modern system of hours have been around since at least ancient Egypt c. 2800 BC. But their system divided "daytime" (after dawn and before sunset) and "nighttime" (after sunset and before dawn) into 12 hours each, whose length would of course vary at different times of the year.
At some point in the intervening ~5000 years, we moved to a system of a day being composed of 24 equal hours that daytime or nighttime could take up a varying quantity of at different times during the year. But I'm having trouble determining at what point this concept first took hold.
There's a related question on here that was closed for being confusing and unclear what exactly was being asked, so to avoid the same fate, here's exactly what I'm asking: when (and by who) was the system established in which each day has 24 hours, each of which are supposed to be of identical length rather than being dependent on varying values such as the length of time that the sun is in the sky?
time-keeping
2
Possible duplicate of When did the current 24-hour day cycle begin?
– Alex
2 hours ago
2
@Alex You mean the one I specifically mentioned in my question and explained why this is different because, unlike that confused question, I have a very clear, articulable understanding of exactly what it is I want to know the answer to? Possible duplicate of that question?
– Mason Wheeler
2 hours ago
2
As the other question was closed for being unclear (which it is, though as far as I can work out it's not asking exactly the same thing as this one), it seems reasonable to leave this one open as it is clear.
– Lars Bosteen
1 hour ago
add a comment |
According to Wikipedia, concepts superficially similar to the modern system of hours have been around since at least ancient Egypt c. 2800 BC. But their system divided "daytime" (after dawn and before sunset) and "nighttime" (after sunset and before dawn) into 12 hours each, whose length would of course vary at different times of the year.
At some point in the intervening ~5000 years, we moved to a system of a day being composed of 24 equal hours that daytime or nighttime could take up a varying quantity of at different times during the year. But I'm having trouble determining at what point this concept first took hold.
There's a related question on here that was closed for being confusing and unclear what exactly was being asked, so to avoid the same fate, here's exactly what I'm asking: when (and by who) was the system established in which each day has 24 hours, each of which are supposed to be of identical length rather than being dependent on varying values such as the length of time that the sun is in the sky?
time-keeping
According to Wikipedia, concepts superficially similar to the modern system of hours have been around since at least ancient Egypt c. 2800 BC. But their system divided "daytime" (after dawn and before sunset) and "nighttime" (after sunset and before dawn) into 12 hours each, whose length would of course vary at different times of the year.
At some point in the intervening ~5000 years, we moved to a system of a day being composed of 24 equal hours that daytime or nighttime could take up a varying quantity of at different times during the year. But I'm having trouble determining at what point this concept first took hold.
There's a related question on here that was closed for being confusing and unclear what exactly was being asked, so to avoid the same fate, here's exactly what I'm asking: when (and by who) was the system established in which each day has 24 hours, each of which are supposed to be of identical length rather than being dependent on varying values such as the length of time that the sun is in the sky?
time-keeping
time-keeping
asked 7 hours ago
Mason WheelerMason Wheeler
1,1602920
1,1602920
2
Possible duplicate of When did the current 24-hour day cycle begin?
– Alex
2 hours ago
2
@Alex You mean the one I specifically mentioned in my question and explained why this is different because, unlike that confused question, I have a very clear, articulable understanding of exactly what it is I want to know the answer to? Possible duplicate of that question?
– Mason Wheeler
2 hours ago
2
As the other question was closed for being unclear (which it is, though as far as I can work out it's not asking exactly the same thing as this one), it seems reasonable to leave this one open as it is clear.
– Lars Bosteen
1 hour ago
add a comment |
2
Possible duplicate of When did the current 24-hour day cycle begin?
– Alex
2 hours ago
2
@Alex You mean the one I specifically mentioned in my question and explained why this is different because, unlike that confused question, I have a very clear, articulable understanding of exactly what it is I want to know the answer to? Possible duplicate of that question?
– Mason Wheeler
2 hours ago
2
As the other question was closed for being unclear (which it is, though as far as I can work out it's not asking exactly the same thing as this one), it seems reasonable to leave this one open as it is clear.
– Lars Bosteen
1 hour ago
2
2
Possible duplicate of When did the current 24-hour day cycle begin?
– Alex
2 hours ago
Possible duplicate of When did the current 24-hour day cycle begin?
– Alex
2 hours ago
2
2
@Alex You mean the one I specifically mentioned in my question and explained why this is different because, unlike that confused question, I have a very clear, articulable understanding of exactly what it is I want to know the answer to? Possible duplicate of that question?
– Mason Wheeler
2 hours ago
@Alex You mean the one I specifically mentioned in my question and explained why this is different because, unlike that confused question, I have a very clear, articulable understanding of exactly what it is I want to know the answer to? Possible duplicate of that question?
– Mason Wheeler
2 hours ago
2
2
As the other question was closed for being unclear (which it is, though as far as I can work out it's not asking exactly the same thing as this one), it seems reasonable to leave this one open as it is clear.
– Lars Bosteen
1 hour ago
As the other question was closed for being unclear (which it is, though as far as I can work out it's not asking exactly the same thing as this one), it seems reasonable to leave this one open as it is clear.
– Lars Bosteen
1 hour ago
add a comment |
1 Answer
1
active
oldest
votes
From Scientific American:
Hipparchus, whose work primarily took place between 147 and 127 B.C.,
proposed dividing the day into 24 equinoctial hours, based on the 12
hours of daylight and 12 hours of darkness observed on equinox days.
Despite this suggestion, laypeople continued to use seasonally varying
hours for many centuries.
In terms of when the 24 hour day began to be relevant to ordinary people in their daily lives, my impression is that this would have come with advancements in mechanical clocks over the course of the Middle Ages and early modern period. See the history of timekeeping devices on Wikipedia, which states:
The appearance of clocks in writings of the 11th century implies that
they were well known in Europe in that period. In the early
14th-century, the Florentine poet Dante Alighieri referred to a clock
in his Paradiso; the first known literary reference to a clock that
struck the hours.
However that article also points out with specific reference to sundials: "The idea of using hours of equal length throughout the year was the innovation of Abu'l-Hasan Ibn al-Shatir in 1371."
Hipparchus was most likely borrowing from the Babylonians and Egyptians.
– Matt Balent
6 hours ago
3
@MattBalent Did they have equal-hour days?
– Mason Wheeler
6 hours ago
3
I'm thinking that Brian Z has a good point here in that the concept of uniform hours would have been largely irrelevant to any culture that didn't have a reliable mechanism for measuring them. Perhaps the concept became more functional with the spread of clock towers and/or hourly bell ringing?
– jeffronicus
55 mins ago
add a comment |
Your Answer
StackExchange.ready(function() {
var channelOptions = {
tags: "".split(" "),
id: "324"
};
initTagRenderer("".split(" "), "".split(" "), channelOptions);
StackExchange.using("externalEditor", function() {
// Have to fire editor after snippets, if snippets enabled
if (StackExchange.settings.snippets.snippetsEnabled) {
StackExchange.using("snippets", function() {
createEditor();
});
}
else {
createEditor();
}
});
function createEditor() {
StackExchange.prepareEditor({
heartbeatType: 'answer',
autoActivateHeartbeat: false,
convertImagesToLinks: false,
noModals: true,
showLowRepImageUploadWarning: true,
reputationToPostImages: null,
bindNavPrevention: true,
postfix: "",
imageUploader: {
brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
allowUrls: true
},
noCode: true, onDemand: true,
discardSelector: ".discard-answer"
,immediatelyShowMarkdownHelp:true
});
}
});
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fhistory.stackexchange.com%2fquestions%2f51311%2fhow-old-is-the-day-of-24-equal-hours%23new-answer', 'question_page');
}
);
Post as a guest
Required, but never shown
1 Answer
1
active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
From Scientific American:
Hipparchus, whose work primarily took place between 147 and 127 B.C.,
proposed dividing the day into 24 equinoctial hours, based on the 12
hours of daylight and 12 hours of darkness observed on equinox days.
Despite this suggestion, laypeople continued to use seasonally varying
hours for many centuries.
In terms of when the 24 hour day began to be relevant to ordinary people in their daily lives, my impression is that this would have come with advancements in mechanical clocks over the course of the Middle Ages and early modern period. See the history of timekeeping devices on Wikipedia, which states:
The appearance of clocks in writings of the 11th century implies that
they were well known in Europe in that period. In the early
14th-century, the Florentine poet Dante Alighieri referred to a clock
in his Paradiso; the first known literary reference to a clock that
struck the hours.
However that article also points out with specific reference to sundials: "The idea of using hours of equal length throughout the year was the innovation of Abu'l-Hasan Ibn al-Shatir in 1371."
Hipparchus was most likely borrowing from the Babylonians and Egyptians.
– Matt Balent
6 hours ago
3
@MattBalent Did they have equal-hour days?
– Mason Wheeler
6 hours ago
3
I'm thinking that Brian Z has a good point here in that the concept of uniform hours would have been largely irrelevant to any culture that didn't have a reliable mechanism for measuring them. Perhaps the concept became more functional with the spread of clock towers and/or hourly bell ringing?
– jeffronicus
55 mins ago
add a comment |
From Scientific American:
Hipparchus, whose work primarily took place between 147 and 127 B.C.,
proposed dividing the day into 24 equinoctial hours, based on the 12
hours of daylight and 12 hours of darkness observed on equinox days.
Despite this suggestion, laypeople continued to use seasonally varying
hours for many centuries.
In terms of when the 24 hour day began to be relevant to ordinary people in their daily lives, my impression is that this would have come with advancements in mechanical clocks over the course of the Middle Ages and early modern period. See the history of timekeeping devices on Wikipedia, which states:
The appearance of clocks in writings of the 11th century implies that
they were well known in Europe in that period. In the early
14th-century, the Florentine poet Dante Alighieri referred to a clock
in his Paradiso; the first known literary reference to a clock that
struck the hours.
However that article also points out with specific reference to sundials: "The idea of using hours of equal length throughout the year was the innovation of Abu'l-Hasan Ibn al-Shatir in 1371."
Hipparchus was most likely borrowing from the Babylonians and Egyptians.
– Matt Balent
6 hours ago
3
@MattBalent Did they have equal-hour days?
– Mason Wheeler
6 hours ago
3
I'm thinking that Brian Z has a good point here in that the concept of uniform hours would have been largely irrelevant to any culture that didn't have a reliable mechanism for measuring them. Perhaps the concept became more functional with the spread of clock towers and/or hourly bell ringing?
– jeffronicus
55 mins ago
add a comment |
From Scientific American:
Hipparchus, whose work primarily took place between 147 and 127 B.C.,
proposed dividing the day into 24 equinoctial hours, based on the 12
hours of daylight and 12 hours of darkness observed on equinox days.
Despite this suggestion, laypeople continued to use seasonally varying
hours for many centuries.
In terms of when the 24 hour day began to be relevant to ordinary people in their daily lives, my impression is that this would have come with advancements in mechanical clocks over the course of the Middle Ages and early modern period. See the history of timekeeping devices on Wikipedia, which states:
The appearance of clocks in writings of the 11th century implies that
they were well known in Europe in that period. In the early
14th-century, the Florentine poet Dante Alighieri referred to a clock
in his Paradiso; the first known literary reference to a clock that
struck the hours.
However that article also points out with specific reference to sundials: "The idea of using hours of equal length throughout the year was the innovation of Abu'l-Hasan Ibn al-Shatir in 1371."
From Scientific American:
Hipparchus, whose work primarily took place between 147 and 127 B.C.,
proposed dividing the day into 24 equinoctial hours, based on the 12
hours of daylight and 12 hours of darkness observed on equinox days.
Despite this suggestion, laypeople continued to use seasonally varying
hours for many centuries.
In terms of when the 24 hour day began to be relevant to ordinary people in their daily lives, my impression is that this would have come with advancements in mechanical clocks over the course of the Middle Ages and early modern period. See the history of timekeeping devices on Wikipedia, which states:
The appearance of clocks in writings of the 11th century implies that
they were well known in Europe in that period. In the early
14th-century, the Florentine poet Dante Alighieri referred to a clock
in his Paradiso; the first known literary reference to a clock that
struck the hours.
However that article also points out with specific reference to sundials: "The idea of using hours of equal length throughout the year was the innovation of Abu'l-Hasan Ibn al-Shatir in 1371."
answered 6 hours ago
Brian ZBrian Z
3,787713
3,787713
Hipparchus was most likely borrowing from the Babylonians and Egyptians.
– Matt Balent
6 hours ago
3
@MattBalent Did they have equal-hour days?
– Mason Wheeler
6 hours ago
3
I'm thinking that Brian Z has a good point here in that the concept of uniform hours would have been largely irrelevant to any culture that didn't have a reliable mechanism for measuring them. Perhaps the concept became more functional with the spread of clock towers and/or hourly bell ringing?
– jeffronicus
55 mins ago
add a comment |
Hipparchus was most likely borrowing from the Babylonians and Egyptians.
– Matt Balent
6 hours ago
3
@MattBalent Did they have equal-hour days?
– Mason Wheeler
6 hours ago
3
I'm thinking that Brian Z has a good point here in that the concept of uniform hours would have been largely irrelevant to any culture that didn't have a reliable mechanism for measuring them. Perhaps the concept became more functional with the spread of clock towers and/or hourly bell ringing?
– jeffronicus
55 mins ago
Hipparchus was most likely borrowing from the Babylonians and Egyptians.
– Matt Balent
6 hours ago
Hipparchus was most likely borrowing from the Babylonians and Egyptians.
– Matt Balent
6 hours ago
3
3
@MattBalent Did they have equal-hour days?
– Mason Wheeler
6 hours ago
@MattBalent Did they have equal-hour days?
– Mason Wheeler
6 hours ago
3
3
I'm thinking that Brian Z has a good point here in that the concept of uniform hours would have been largely irrelevant to any culture that didn't have a reliable mechanism for measuring them. Perhaps the concept became more functional with the spread of clock towers and/or hourly bell ringing?
– jeffronicus
55 mins ago
I'm thinking that Brian Z has a good point here in that the concept of uniform hours would have been largely irrelevant to any culture that didn't have a reliable mechanism for measuring them. Perhaps the concept became more functional with the spread of clock towers and/or hourly bell ringing?
– jeffronicus
55 mins ago
add a comment |
Thanks for contributing an answer to History Stack Exchange!
- Please be sure to answer the question. Provide details and share your research!
But avoid …
- Asking for help, clarification, or responding to other answers.
- Making statements based on opinion; back them up with references or personal experience.
To learn more, see our tips on writing great answers.
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fhistory.stackexchange.com%2fquestions%2f51311%2fhow-old-is-the-day-of-24-equal-hours%23new-answer', 'question_page');
}
);
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
2
Possible duplicate of When did the current 24-hour day cycle begin?
– Alex
2 hours ago
2
@Alex You mean the one I specifically mentioned in my question and explained why this is different because, unlike that confused question, I have a very clear, articulable understanding of exactly what it is I want to know the answer to? Possible duplicate of that question?
– Mason Wheeler
2 hours ago
2
As the other question was closed for being unclear (which it is, though as far as I can work out it's not asking exactly the same thing as this one), it seems reasonable to leave this one open as it is clear.
– Lars Bosteen
1 hour ago