Talk:24-hour clock

Invalid date and time formats in the conventional clocks

Dates, as the day 0, the 29 Februarys on the common years, 30 February, 31 November, the day 32, the month 0 and the month 13, for example, are invalid. Times, as 23:59:60, 23:60, 24:00:00 and 24:00, for example, also are invalid. The conventional clocks do not accept these invalid formats.

2804:18:65:718B:2:2:4791:4BB8 (talk) 10:47, 18 September 2022 (UTC) — Preceding unsigned comment added by 177.26.224.147 (talk)

What does this have to do with this article? Month, for example, doesn't mention "the day 32" because what doesn't exist isn't relevant on such an article. What changes are you proposing for this article, and what reliable sources do you have to support your proposed changes? - Aoidh (talk) 20:43, 18 September 2022 (UTC)

The conventional digital clocks mark "errors" when the invalid dates or the invalid hours are adjusted. The second format goes by 00 to 59, the minute format goes by 00 to 59 and the hour format goes by 00 to 23. The day format goes by 01 to 31 and the month format goes by 01 to 12.

177.26.224.147 (talk) 20:54, 18 September 2022 (UTC)

What do months and days have to do with the 24-hour clock, this article? Anastrophe (talk) 21:19, 18 September 2022 (UTC)

I'll ask again IP editor: What, specifically, are you suggesting to be changed in the article, and what reliable sources do you propose that support your contentions? Anastrophe (talk) 23:25, 18 September 2022 (UTC)

The conventional digital clocks contain hour values from "00" to "23", minute from "00" to "59" and second from "00" to "59". Many clocks contain the formats "HH:MM:SS" ("00:00:00" and "23:59:59", for example) and "DD-MM-YY" ("01-01-00", "29-02-00" and "31-12-99", for example).

179.98.235.119 (talk) 20:57, 29 October 2023 (UTC)

Variety of English

This post appeared on my talk page:

The edit of 08:21, 7 June 2003 introduces the word "endeavour." 156.61.250.251 (talk) 16:14, 27 July 2023 (UTC)

I acknowledge this predates the use of American English from 2005 that I found. I will link to the edit. I intend to add the {{Use British English}} template to the article and check the spelling. Jc3s5h (talk) 17:47, 27 July 2023 (UTC)

@Jc3s5h: it's a bit more complicated than that since per MOS you need to find the first non-stub revision with a variety that can be identified, and the revision in question fails both prongs; it is still a stub and could as easily be Canadian English as South African or a dozen other varieties (this is why the article is at humour and not humor despite having been started at the latter title). Additionally, 156.61.250.251 was evading a block, and probably just trying to be disruptive.

Anyway, I don't care enough to look through the history to see what this should be tagged as, but if you want to revert to before the sock edits feel free. 74.73.224.126 (talk) 13:00, 14 August 2023 (UTC)

Fleming edits

So here is the full quote from Fleming [1]: "It is proposed to take as the unit-measure of time, the artificial day known as the mean solar day. This unit to be divided into twenty-four equal parts, and these, again, into minutes and seconds by a standard timekeeper or chronometer, hypothetically stationed at the centre of the earth."

@Jc3s5h what part about this does not support that Fleming's system is not based on keeping time at the center of the Earth? Mathnerd314159 (talk) 01:32, 10 January 2024 (UTC)

a further quote from the next page:

"the time indicated by the Standard Chronometer would have no special relation to any particular locality or longitude : it would be common and equally related to, all places ; and the twenty-four sub-divisions of the day would be simply portions of abstract time.

The standard time-keeper is referred to the centre of the earth in order clearly to bring out the idea, that it is equally related to every point on the surface of the globe." Mathnerd314159 (talk) 01:34, 10 January 2024 (UTC)

User: Mathnerd314159 has tried to make several edits stating that Sandford Fleming "proposed a single 24-hour clock for the entire world, located at the centre of the Earth, not linked to any surface meridian", and cited a work by Fleming to support the edits. But the edits do not correctly describe Fleming's work. Fleming's writing is a thought experiment, rather than a practical clock. The face of the hypothetical clock would be parallel to the equator, and would be arranged so the hour hand points to the meridian where noon is occurring. He proposed the hours of the day, and the meridians, be designated with 24 letters of the alphabet, with G being assigned to Greenwich.

Since this scheme is seldom mentioned, and it would take considerable text to explain it, I don't think this scheme should be mentioned in the article. Additional reasons to reject it are

• Now that that Einstein's General Theory of Relativity is available, we know that time passes more slowly than it would if the Earth could be eliminated, but if time were kept at the location where the center of the Earth would have been.
• "Terrestrial Time" now has a specific meaning, which is different from what Fleming meant.
• The whole apparatus of placing the timekeeper at the center of the Earth does not improve the explanation, and just causes confusion.
• A short quote does not adequately convey the scheme, it's necessary to read the whole memoir to understand it.

Jc3s5h (talk) 01:54, 10 January 2024 (UTC)

I haven't made these edits, I have been reverting IP ‎71.195.46.250's edits (was that you?) that changed it from the original phrasing "a single 24-hour clock for the entire world, located at the centre of the Earth, not linked to any surface meridian" to a new phrasing "a single 24-hour clock for the entire world, referenced to a standard meridian". The original phrasing was added by user @AndrewNJ in this edit 5 years ago. As this original phrasing has stood the test of time, the WP:BURDEN is on you to show that the new phrasing is correct. You have not presented any sources that show Fleming supported a 24-hour clock referenced to a standard meridian; indeed, the present sources show the opposite - "Time Lord" says Fleming proposed an imaginary chronometer in the center of the Earth, and "Time-reckoning for the twentieth century" credits Mr. Christie and the conference with proposing the meridian time. Even if there is something in the "Time-reckoning" source that shows Fleming supports the meridian time, Fleming certainly did not imagine a standard meridian in 1876 as the sentence's context suggests - it was later, in 1884, at the conference.

As far as the scheme being seldom mentioned, "Time Lord" mentions it for one. It is really Fleming's signature work. Britanica says "Fleming advocated the adoption of a standard, or mean, time with hourly variations from it according to a system of time zones."; admittedly it is a bit oblique as to whether this standard time is measured at the center of the earth.

Now if you don't want to mention the scheme, there are several places to link to - Sandford Fleming#Inventor of world time, Universal Time#History, and Time zone#Worldwide time zones. Maybe change the whole paragraph to "Sandford Fleming was an early proponent of using the 24-hour clock as part of a programme to reform timekeeping, see Sandford Fleming § Inventor of world time. The Canadian Pacific Railway..." Mathnerd314159 (talk) 03:10, 10 January 2024 (UTC)

A source mentioned in Sanford Fleming is the first endnote,

• Creet, Mario (1990). "Sandford Fleming and Universal Time". Scientia Canadensis: Canadian Journal of the History of Science, Technology and Medicine. 14 (1–2): 66–89. doi:10.7202/800302ar.

This source gives a good overview of how Fleming's activities and papers lead to the adoption of universal time, time zones, and a prime meridian for the world (although Fleming first advocated a prime meridian through the Bering Strait). This article supports the statement currently in the article.

You're correct that the current endnotes, no. 15 and 16, aren't very satisfactory. I don't think their really adequate for either the older or newer version of the article. The first does not have the pages of interest online, so I can't evaluate it. The second, by Blaise, gives a rather oblique description of the paper on "Terrestrial Time", making it impossible to understand "Terrestrial Time" from that book. It is useful for this discussion in that it describes "Terrestrial Time" as "far too difficult for commercial adoption in its day" and goes on to say that in 1878 Fleming published a second, simplified, paper which abandoned the buried clock and proposed a surprising prime meridian. (I imagine that's the one through the Bering Strait.) Jc3s5h (talk) 04:46, 10 January 2024 (UTC)

Reading further in the paragraph, I see the Creet source I mentioned is already cited. Jc3s5h (talk) 16:25, 10 January 2024 (UTC)

Date format for article

As far as I can find, the first version of the article to use an acceptable date format used several different date formats in the same edit. The date format of the article is still inconsistent. For no particular reason, I suggest the "day month year" format for the article. Jc3s5h (talk) 21:29, 11 January 2024 (UTC)

Since there is no response after 5 days I will make the change. Jc3s5h (talk) 18:05, 16 January 2024 (UTC)

Wee hours

An IP editor has been removing the reference to wee hours, despite the fact that their rationale is directly and unambiguously contradicted by the sources that are already in the article supporting the content. Their rationale is that 'wee hours' cannot apply as it is defined as the early hours of the morning and therefore cannot be accurate as they contend that 00:00 until 06:00 is only postmidnight, not part of the morning. I could find no source that supports this claim, and indeed that usage of 'early hours of the morning' is the same reason that 02:00 is also referred to as 2 in the morning, or 03:00 as 3 in the morning. Reliable sources routinely refer to this window of time as being in the morning, further demonstrating that the rationale used to remove this content is not reflective of actual usage or reliable sourcing. - Aoidh (talk) 21:42, 20 June 2025 (UTC)

Based on the user's edit history, they don't appear to be interested in good faith edits, or following policies, and instead pushing their opinion of what is "right". If they keep up, temporary page restriction might be needed. There have been a number edits over the last few months by apparently the same editor on different IP addresses. Disruptive editing like this just adds housekeeping chores for those who put effort into building the encyclopedia while following policies. cheers. anastrophe, an editor he is. 22:01, 20 June 2025 (UTC)

@anastrophe The accusations you made against me are serious. I contribute in good faith and I have not committed any vandalism.

@Aoidh About the 24-hour clock page, I just said the correct thing, that the period between 00:00 to 06:00 is just "postmidnight", not "morning".

If the day has 24 hours and 4 periods/parts, then each part/period has 6 hours:

• Postmidnight = 00:00 until 06:00

• Morning = 06:00 until 12:00

• Afternoon = 12:00 until 18:00

• Evening or night = 18:00 until 00:00

Remembering that I just want to contribute, I don't want to say things in a "popular" way, since it is incorrect to say that 00:00 until 06:00 is part of the morning.

I will not edit the page temporarily, I want to reach a consensus.

I know that the sources state that 00:00 until 06:00 is part of the morning, but I believe that is incorrect.

To conclude, I agree that the terms daytime (06:00 until 18:00) and nighttime (18:00 until 06:00) are correct, but I don't think it's necessary to put them in the table. It's more interesting to put the periods in 4 parts and not in 2 parts. 168.232.221.120 (talk) 00:23, 21 June 2025 (UTC)

If the day has 24 hours and 4 periods/parts Do you have a citation for the day being so divided? Guy Harris (talk) 01:03, 21 June 2025 (UTC)

"I contribute in good faith and I have not committed any vandalism." I said nothing about vandalism. I said it was based on your edit history, which shows repeated changing of content to match your opinions (because you've never offered reliable sourcing to back up the changes), removing material along with the source that supports it, and edit warring when reverted. At best I can recommend familiarizing yourself to some degree with WP's policies and guidelines, though to be fair, that's an enormous corpus to digest. But there are standards that apply when editing here, and those standards must be followed. If I take you at your word that your intentions are in good faith, then I would recommend:

• Review the Simplified ruleset as a start in becoming familiar with the basic rules and policies;
• Visit the Teahouse, where you can engage with experienced editors for advice and even mentoring to learn how to edit without causing disruption. cheers. anastrophe, an editor he is. 02:25, 21 June 2025 (UTC)

For me the question is not so much whether "wee hours" is correct as to whether it is relevant to the article. To recap, two months ago, this article just had a simple table, showing the correspondence between a 24-hour clock and a 12-hour clock. And then we got Part of the day and "general period of the day", both by IP's without comment. I don't think either of these columns actually explains anything relevant to a 24-hour clock, especially considering that the main text of the article doesn't discuss this division. And with the current 4-column format, the table ends up taking half the page width (or more depending on appearance settings) - it just looks ugly. Mathnerd314159 (talk) 01:41, 21 June 2025 (UTC)

Now there is actually a place where this information could go: Day#Parts. But not this article. Mathnerd314159 (talk) 01:52, 21 June 2025 (UTC)

Agree that the 'parts' of the day are irrelevant to the topic of this article. cheers. anastrophe, an editor he is. 02:27, 21 June 2025 (UTC)

Especially given that, for example, "Morning" is arbitrarily stated as beginning at 6:00, without a citation; Morning states that it is "either the period from sunrise to noon, or the period from midnight to noon." It continues "In the first definition it is preceded by the twilight period of dawn, and there are no exact times for when morning begins (also true of evening and night) because it can vary according to one's latitude, and the hours of daylight at each time of year. However, morning strictly ends at noon, when afternoon starts."; the sun doesn't reliably rise at 6:00 every day. Evening is similarly not definitive as to when evening begins.

So let's stop having the table arbitrarily divide the day into four 6-hour periods. Guy Harris (talk) 02:42, 21 June 2025 (UTC)

I think it's reasonable to remove the Part of the day and Period of the day parts entirely. Calling 5pm daytime and 6pm nighttime is misleading at best. Unless there's some international definition that I'm unaware of, when night begins changes depending on what time of year it is, and even on the same day it depends on where in the world you are at that time and how you define what night is, which varies depending on the context. - Aoidh (talk) 12:06, 21 June 2025 (UTC)

I know there's already a column with the 12 hour clock times, but rather than times of day we could have the column split the day between ante meridiem and post meridiem? Nil🥝 (talk) 13:06, 21 June 2025 (UTC)

In many countries, the day is divided into 4 periods/parts.

In Brazil, the country where I live, the day is divided into 4 periods/parts, madrugada (postmidnight), manhã (morning), tarde (afternoon) and noite (evening/night)

In the sources (external links) presented, it is proven that the day is divided into 4 periods/parts: postmidnight (00:00 to 06:00), morning (06:00 to 12:00), afternoon (12:00 to 18:00) and evening/night (18:00 to 00:00).

And I used logical reasoning, if the day has 24 hours and 4 periods/parts, then the fair thing is that each one has 6 hours.

I think it is fair to keep the periods/parts of the day in the timetable on the 24-hour clock page, even though they are also placed on another cited page: Day#Parts.

Just remember that dawn/sunrise and dusk/sunset do not have fixed times, unlike noon/midday (12:00) and midnight (00:00). So it would be confusing if one period had more hours than the other. 168.232.221.7 (talk) 15:51, 21 June 2025 (UTC)

If the day is divided that way in certain countries, then the prose could (if properly sourced and WP:DUE) mention that this is the case in those countries, but much of the world does not delineate it so, especially in a way that can be placed on a table for the reason already given (6pm is not 'night' everywhere at all times). Those columns of the table are unsourced and misleading/inaccurate. That dawn/sunrise and dusk/sunset do not have fixed times is precisely why that content does not belong on a table suggesting that they do have fixed times. - Aoidh (talk) 16:04, 21 June 2025 (UTC)

In the sources (external links) presented, it is proven that the day is divided into 4 periods/parts More precisely, it is proven that in Brazil, the day is divided into 4 periods/parts. It proves nothing about how the day is divided in China, India, the US, Germany, France, Italy, Japan, Korea, Nigeria, Russia, the UK, etc..

I think it is fair to keep the periods/parts of the day in the timetable on the 24-hour clock page, even though they are also placed on another cited page: Day#Parts. The periods/parts of the day in Day#Parts are not the ones used in Brazil; they are "Daytime", "Twilight", and "Night", and do not have fixed boundaries, not even noon - they're based on the sun, and thus differ based both on latitude and time of year. I see nothing special about Brazil's division of the day, just as I see nothing special about China's, India's, the US's, Germany's, France's, Italy's, Japan's, Korea's, Nigeria's, Russia's, the UK's, etc. divisions of the day, to make any of those belong in the table. Guy Harris (talk) 16:32, 21 June 2025 (UTC)

References