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I am not convinced that this trivia of furlong per fortnight is often misquoted, as I have, as far as I recall, never heard it quoted at all. It debases Wikipedia to have such a prominent bit of trivia - these silly examples may be accurate, but they are not useful or relevant. The point is made.

I suggest that it be severely trimmed down, leaving silly examples to the reader's imagination.


      • Not everything needs to be useful or relevant, Spenny, lighten up! I enjoyed it.

- CharlieTuna

My first exposure to this was around 25 years ago in a Unix fortune cookie (a small program that displays a pithy or witty saying often run as part of the login process on Unix systems). As I recall it stated: "Data will always be expressed in the least useful units. For instance, speed will be expressed in furlongs per fortnight".

SurrealPenguin (talk) 08:41, 22 April 2008 (UTC)

Furlongs per Fortnight - Minute hand speed[edit]

I particularly liked the reference to a furlong per fortnight, since that was actually the reason I was looking up the exact distance of a furlong. I've heard this phrase a number of times, being an engineer myself, and wanted to know how to post the speed limit on a highway properly in the appropriately unintelligible units :-D...

Also - I noticed the following section:

"one furlong per fortnight is 0.166 millimetres per second, which would be barely noticeable to the naked eye (the tip of an hour hand on a clock, measuring 3.75 feet in length, travels at about 1 furlong per fortnight — as does the tip of a second hand 1/16 of an inch in length)."

Missed a much more reasonable reference of the tip of a minute hand, 3.75 inches in length!


—The preceding unsigned comment was added by (talk) 06:34, 27 February 2007 (UTC).

I have heard F/F quoted. Never misquoted, though. Does the author have a reason why it is "misquoted"? Irrelevant or useless is fine. Simultaneously prescriptive, though?Still A Student 01:47, 17 March 2006 (UTC)

I have never seen it misquoted, so I'm removing that. --Psm 18:30, 14 July 2006 (UTC)

I have added back the trivia section on Furlong per Fortnight since it is a part of the information on the Furlong and a part apparently many people have an interest in. I will add, i have never heard it "misquoted." Gingermint (talk) 20:54, 4 October 2009 (UTC)

F/F silliness[edit]

My first, and only, exposure to Furlongs/Fortnight was in a humorous short essay about engineers. It stated that engineers would always provide data in a form conveying the least meaning. E.g. velocity measured in furlongs per fortnight.

I don't believe there is anything inherently wrong with including the lighter side of a topic in an encyclopedia. In fact, the term "encyclopedia" almost demands that all aspects be considered.

Knowledge that brings a smile is still knowledge.

Phlogiston Warrior

I would like to see two examples add to the F/F entry to add some relevancy to the unit, as the ones described there demonstrate why it's irrelevant now. The two examples I would include would be human march speed and speed of travel by horse, as I'm pretty sure that these speeds figured in F/F would've been handy to merchants, couriers, and military commanders back in the Middle Ages (in fact, I came here from fortnight following a link from the Battle of Stamford Bridge, where King Harold fought a full fortnight before racing to fight the Battle of Hastings.)--YoungFreud 20:22, 25 September 2006 (UTC)
"F/F" is not a practical unit for expressing marching speeds, or travel speed for horses. It's too small a unit. Snails travel at approximately six furlongs per fortnight, which is basically one millimeter per second, so it's not a rate, it's a punchline. People march at a rate of approximately 24 furlongs (three miles) per hour, or about 8000 furlongs per fortnight. It's pointless to choose these units to express marching rates, because nobody would march continuously for a fortnight. That's why it's a joke. Silarius 22:28, 15 June 2007 (UTC)

Bible References[edit]

I removed the following text from the Trivia section:

In the biblical book of Revelation (Ch 21:16), the King James version of the New Testament describes the Holy City of New Jerusalem as being 12,000 furlongs cubed. This works out to be almost 23½ cubic miles, 100 km³, or the volume of a single structure over four times the height of the Empire State Building covering the entire island of Manhattan

In case y'all think that was wrong, put it back. I'm removing it for several reasons, but primarily because the Bible reference in question is, indeed, from the King James Version where "furlong" replaced the actual unit (the Greek stadion). (Source: New American Bible.) Also because this "trivia" has nothing to do with the concept of furlong (or stadion) at all.

Prime number 11?[edit]

I'm totally stumped as to what this parenthetical comment has to do with the furlong. Someone's going to have to patiently explain it and not expect the meaning to immediately jump out at the reader (at least this reader). -- 16:47, 21 July 2006 (UTC)

The prime number 11 comes from the reference to the rod, which is 11/2 yards. The least common multiple of this with the Roman 1000 passus (5 feet each) made it reasonable to redefine a mile to a number that was a multiple of 11 - 5280 feet is 320 rods. -KevinM
The question then becomes: why is a rod eleven half-yards? Urhixidur 12:45, 27 February 2007 (UTC)
A rod (unit) is 16.5 feet. This is 5.5 yards. A rod length is not derived from yards but from furlongs and chains, of which it is a convenient submultiple. A rod is also sometimes called a pole, and my Dad told me of actually measuring off land by flipping off a 16.5 foot pole end over end while walking the boundaries of a rented field, to be sure it was the size described. An acre is the equivalent of four poles by 40 poles, or one chain by four chains, if I remember correctly. A farmer might not own a Gunter's chain, but he probably had lots of poles handy. I do not see why any mention of 11 being a prime number belongs in the article because of this. Edison 21:28, 23 May 2007 (UTC)
After inch, foot, and yard, then the chain becomes the next unit of measure. I have a copy of a map of Sydney, New South Wales, made about 1820. The distance reference line is marked off in chain units with the 10 chain and 20 chain marks having the appropriate number above them. It's rather curious why 22 yards was chosen as being a chain (and not 20, or 24, or 25 yards). However, having chosen 10 chains to be a furlong (and they would have had some idea how long this should be, as it was the most economical length for a furrow), and wanting one mile to be eight furlongs, then 80 chains would equal one mile. The Roman mile was 5000 feet and they would want their "new mile" to be close to this. They would also want the chain (in feet) to be divisible by three so that it was an even number of yards. The only possibilities would be 60 feet (with a mile of 4800 feet), 63 feet (with a mile of 5040 feet; but 21 yards is difficult to divide by foru), or 66 feet (with a mile of 5280 feet and a chain of 22 yards; not so hard to divide into four rods). I'm sure the figures of 66 and 22 would have had some appeal in themselves.
Queen Elizabeth I decreed this to be the length of the English mile. Also, perhaps we should not forget that the length of a cricket pitch is 22 yards.(DaveNed88 (talk) 02:49, 30 March 2010 (UTC))

Size of an acre?[edit]

The image that goes with the article shows that one acre = one rod x one furlong, but that would be 1/4 acre. Is the image wrong?


Autopilot (talk) 02:34, 24 August 2008 (UTC)

I suspect the little mark above the word "rod" is supposed to indicate that the distance between the two little horizontal line in the mark, so it looks as though that edge of the acre might be four rods, which would be right. Also, the overall shape of the acre is about right. The long edge is about 10 times the short edge. But the little mark really is inadequate and the image should be improved. --Gerry Ashton (talk) 05:06, 24 August 2008 (UTC)
You're right that the little mark is showing the length of a rod (compared to a chain). When the full image is viewed, the small grid lines that show the four rods is visible. But when it is scaled down, as it is on the furlong page, the grid lines are blended out of view. Perhaps changing the label to read "4 rods" and underneath it "1 chain" would make it clearer. --Autopilot (talk) 12:15, 24 August 2008 (UTC)
Maybe just "4 rods" because I don't think the chain is nearly as ancient as the other units shown in the diagram. --Gerry Ashton (talk) 15:54, 24 August 2008 (UTC)
Thanks for the tip.Unitfreak (talk) 04:42, 27 August 2008 (UTC)

International vs. survey foot[edit]

The footnote tries to justify the use of the international foot (0.3048 m) in defining the furlong, but the link offered makes no mention of the furlong specifically, and it contains the exception that the foot (and derived units) used for geodetic surveys would continue to be 12003937 m.

I've seen more than my share of land deeds and know that customary surveying units that are only still used for surveying land, such as the chain and rod, are emphatically defined by the survey foot of 12003937 m, because of the aforementioned exception for geodetic data. This naturally also includes the acre (based on the square survey foot), as well as the Public Land Survey System divisions of sections and townships. While I can't recall seeing a deed mentioning tracts of land measured in furlongs specifically, if we're going to relate the furlong to rods, chains and acres as well as point out their use in meting out city blocks (which would be also be meted in survey feet), I think it'd be more accurate to describe it as 792.0003937 m exactly.

(Also, it looks like the pages on the rod and the chain need to be changed, too...) Guppy313 (talk) 04:50, 19 February 2009 (UTC)

First of all, this discussion only applies to the U.S.A., since the American survey foot only exists there. If you look at the foot (length) article, you will find this quote from the National Geodetic Survey:

Within the legislation, the U.S. Survey Foot was specified in 11 states and the International Foot was specified in six states. In all other states the meter is the only referenced unit of measure in the SPCS 83 legislation. The remaining 19 states do not yet have any legislation concerning SPCS 83.

True, this does not directly address the meaning of feet, rods, and acres that occur in deeds, but it makes it plain that either might be used, depending on the state. Furthermore, the only customary unit that would still be in use in a precision application is the foot (and maybe the acre). --Gerry Ashton (talk) 05:12, 19 February 2009 (UTC)
In answer to your first, while it's true this would only apply to the U.S.A., who else still uses the furlong for purposes of government and trade? Granted this is only in the realm of real estate, but it's my understanding that the rest of the world is compelled to use metric in this field.
The block quote you provided above was concerned with the adoption of the metric-only North American Datum of 1983 and how the states chose to specify the conversion factor from the meters of the Datum into their own State Plane Coordinate Systems. The high-precision Datum is useful for engineering projects such as laying road, placing building foundations, or determining the location of mineral deposits. However, the Datum is not the only coordinate system used (otherwise there likely wouldn't have been such lackluster adoption according to a document written in 1991, considering that the previous Datum was from 1927), and for purposes such as real estate, where a chain of acquisition for a particular parcel of land needs to be determined based on prior deeds, the coordinate systems used predate the 1959 introduction of the international foot. The PLSS, for example, predates the development of the meter itself.
Even urban areas which tend to be independent of such statewide coordinate grids use the survey foot to determine legal property ownership. Every parcel of land that was meted and platted out at some point before 1959 necessarily uses the only foot that was available at the time, what we've come to call the survey foot. This includes all of the American cities that are listed in the "Uses" section with their one-furlong blocks.
As to the use of these more archaic units in "precision applications," absent a compelling reason to adopt a different system of measure (e.g. a law requiring meters, or a new subdivision meted in decimal feet), deed descriptions will continue to use the language and units of prior deeds in order to demonstrate that the same parcel of land is being described, maintaining a defensible legal chain of custody. If a rural plot was originally meted in chains and links, or an urban plot in feet, inches and lines, future deeds for that land will continue to use those same units. Consider the arpent, which still turns up in American deeds in spite of American acquisition of the described lands centuries ago.
Arbitrarily changing definitions of the foot (and units derived from it) has the effect of changing property lines and, in the United States, even municipal boundaries. Even in midsized states, the point of origin for coordinate systems like the PLSS can be hundreds of kilometers away, creating propagated errors as large as several meters, more than enough for a stream or a well to change owners (and changing the taxable value of the parcels along with it). This was why the survey foot was maintained after 1959 to begin with.
Anyway, to sum up my longwindedness (too late!), outside of a horse track, the furlong is only currently encountered in the United States (other jurisdictions using compulsory metric), and the only field of study it would be encountered in is land surveying (other fields using compulsory feet and miles). Again, I don't know if the furlong itself is still used in land surveying (a quarter of a quarter of a quarter of a section can be described as one furlong square), but if it is, as the furlong's sole remaining legal use in the one country where it's still permitted, it's defined as 7920003937 m. Guppy313 (talk) 18:28, 19 February 2009 (UTC)
The republication of an announcement in the Federal Register of January 22,1975 (40 FR 3486) on the NIST Web site (and linked in United States customary units) states
Metric equivalents of all surveyor’s units, e.g., links, rods, and chains, arc derived from thc survey foot.
NIST Special Publication 811 (2008 version), Appendix B, B.6 U.S. survey foot and mile, specifically indicates that the furlong is based on the survey foot. Absent something convincing to the contrary, I think we should revise this article accordingly. JeffConrad (talk) 09:27, 28 April 2011 (UTC)
The site of the National Geodetic Survey seems to be down right now, but they have a page, cited at foot (unit), which indicates how many states specify that when surveys are carried out in state plane coordinates, whether the units used should be meters, U.S. survey feet, or international feet (or allow the surveyor to choose). There are some states in each category. Further, NIST may say that furlongs are surveyor's units, but except for a few deeds from decades or centuries ago, that just isn't so. Surveyors use either meters or feet.
So yes, the article should be revised, but it shouldn't give undo weight to a definition that applies only in the U.S. and isn't generally understood or applied even there. Jc3s5h (talk) 12:24, 28 April 2011 (UTC)
Agree with you and Guppy313 that furlongs are generally not used by anyone other than horses (a search for “furlong” on the NGS Web site turns up nothing, and it’s not mentioned in NIST SP 330, either). It seems to me that we err in equating imperial units and U.S. customary units in the first sentence, which is incompatible with what is said in United States customary units#Units of length. I don’t think there′s much disagreement on the relationships of the furlong, chain, rod, and link, but we need an authoritative definition (or definitions) for this group; I doubt we want to do it on a state-by-state basis, so at least for the U.S., NIST (or another federal agency of equivalent stature) might seem a good starting point. JeffConrad (talk) 00:50, 29 April 2011 (UTC)
I can find nothing in the way of the definition of an “international furlong”. The Weights and Measures Act 1985 (U.K.) gives the furlong in terms of the international yard, equal to 0.9144 metre; as previously noted, NIST Special Publication 811 gives the furlong in terms of the U.S survey mile (or whichever survey unit you prefer). So it would appear that we have two citable (but different) definitions, neither apparently predominant. It seems to me that there is considerable advantage in maintaining the familiar (and simple) relationships among the furlong, chain, rod, link, yard, and foot; the best approach may be similar to that used in Mile:
The exact conversion of the mile to SI units depends on which definition of the yard is used.
We could then cite the U.S. and U.K. definitions, as well as any others for which reliable sources can be found. JeffConrad (talk) 02:22, 1 May 2011 (UTC)
That approach sounds good to me. Jc3s5h (talk) 14:39, 1 May 2011 (UTC)

Edit of 2 May 2011[edit]

I’ve put the material in a new section at the end because it’s probably far more than most readers will care about—see if this works. I used scare quotes for the “international” value because there really is no such thing, and every alternative definition I could think of was awkwardly verbose.

It appears that we have a similar issue with most of the units that NIST define in terms of the survey foot; although it would be a simple matter to copy and slightly revise the material I’ve added here, doing so would seem needless repetition with the possibility of inconsistencies resulting from subsequent edits. But I’m not sure the topic justifies a separate article. Thoughts, anyone? JeffConrad (talk) 03:09, 2 May 2011 (UTC)

Spelling and metrication[edit]

See a discussion under the same heading at WT:Manual of Style (dates and numbers). Jc3s5h (talk) 17:30, 9 June 2010 (UTC)

I dont know about other pages but per WP:RETAIN the first major edit was in British English on 17:49, 8 June 2004. Not only that I would claim that this article passes MOS:TIES "An article on a topic that has strong ties to a particular English-speaking nation uses the English of that nation." Because while this is a well-known unit of measure to the general public in the U.K. it is virtually unheard of in the United States. -- Phoenix (talk) 03:22, 10 June 2010 (UTC)
In the U.S.A. it is known in the field of horse racing. Is it used for anything else in the U.K.? Jc3s5h (talk) 12:19, 10 June 2010 (UTC)
With the exception of horse racing, mostly street names and the length of some city blocks, but living in both countries I can say that it is a known length in the U.K. and an unknown one in the U.S. -- Phoenix (talk) 19:39, 10 June 2010 (UTC)
I can say the furlong is a known length in the U.S. and it even sees use on the Interstate Highway System since 1/8 mile increments are occasionally signed (although I have never seen 1/8 mile, think they were 3/8 and 5/8 that I saw). I've seen several old British signs that are still in place along roadsigns of public roads in the U.K. that a buddy of mine there showed me. Perhaps if he or the author consents, I could put them up here? Think one was furlongs, and there may or may not have been one that was in miles and eighths.
Also, does anyone have some information about the Burmese furlong sign. Some Internet armchair expert was claiming they were all kilometers "now" which I had assumed to be correct, until seeing an even newer post, less than six months old talking about biking there and how "everything was still in miles [and furlongs] there. If we had a more current picture of the signs there, even if it's the same damned toll plaza, that would go a long way. Its government Web site, at least in English, is, shall we say, lacking?

Surveyor792 (talk) 05:59, 29 September 2013 (UTC)


"Metricized" is the word, and "metricated" is a nonword that is not found in any dictionaties. The lengths of horse races in Australia were "metricized". It is astonishing that people want to make up and use nonwords in English. (talk) 13:16, 7 October 2013 (UTC)

Might want to check your facts before you make spurious assertions. Metrication[1] [2] [3] and it is worth noting there is a subtle difference in meaning between metricate and metricize. olderwiser 14:27, 7 October 2013 (UTC)
O.K. wise guy: Try, which draws its vocabulary from numerous dictionaries, and "metricated" is NOT in it. Dummy, accusing me of not checking my facts. You should be ashamed of yourself. (talk) 15:05, 7 October 2013 (UTC)
"Metricate" is most certainly in the Oxford English Dictionary, even in the concise version that I have here. DOwenWilliams (talk) 15:17, 7 October 2013 (UTC)
"Metricate" is also in DOwenWilliams (talk) 15:11, 9 October 2013 (UTC)
@ Speaking of dummies, does have an entry for 'metricate. olderwiser 15:57, 9 October 2013 (UTC)
It includes "metricate", but not "metricated". People who don't know how to use dictionaries may get confused. DOwenWilliams (talk) 21:09, 9 October 2013 (UTC)

Use the right verb[edit]

Five furlongs IS approximately 1.0 kilometre, and not "are".
Multiples of units and numbers themselves are treated as singular in English.
For example: 5,280 feet is one mile. 13 is the number of original states in the United States. 440 yards is one quarter mile. Plural verbs are not used in these. (talk) 14:15, 7 October 2013 (UTC)

13 is a (singular) number. Feet are plural. Singular/plural usage in this context, and in others, is variable. British usage tends to use plural verbs with collective nouns, e.g. "The government are planning to ban baseball". DOwenWilliams (talk) 15:13, 7 October 2013 (UTC)

Exact conversion factors[edit]

Because of the exact conversion factor of one meter = 39.37 inches, the conversion between inches and millimeters works out to be one inch = 25.4000508, with more decimal places. Hence. 25.4 is not an exact conversion, but close enough for all practical purposes. Rather than one furlong = 202.168 meters exactly, one furlong = 201.1684 meters, approximately. (talk) 15:01, 7 October 2013 (UTC)

39.37" is a convenient approximation, not internationally accepted as exact. DOwenWilliams (talk) 15:07, 7 October 2013 (UTC)


I've seen square furlongs used as a unit of area when square miles are too large to measure in. On a trip to St Mary's in the Scilly Isles the tourist maps grid is in square furlongs (1/8 sq mi). Might be worth adding to usage. (talk) 23:05, 27 July 2014 (UTC)

A square furlong is 1/64 square mile, not 1/8 square mile. (talk) 06:04, 30 September 2014 (UTC)
Either way, this is an unusual concept and I think we need a [{WP:RS]] for this before adding anything on it at all. Montanabw(talk) 03:51, 1 October 2014 (UTC)