# Knot, Fathom and League **URL:** \ **Category:** Cecil's Columns/Staff Reports\ **Created:** [September 24, 2000, 2:51am UTC](https://boards.straightdope.com/t/knot-fathom-and-league/34329 "2000-09-24T02:51:20Z")\ **Posts on this page:** 11\ **Page:** 1
**Author:** ![KarlGauss](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/karlgauss/32/3713_2.png) [@KarlGauss](https://boards.straightdope.com/u/KarlGauss)\ **Post date:** [September 24, 2000, 2:51am UTC](https://boards.straightdope.com/t/knot-fathom-and-league/34329/1 "2000-09-24T02:51:20Z")
> [@](#): > > Cecil said, **“League–three statute miles or approximately 483 meters”**. Shouldn’t that be 483 **0** meters? ---
**Author:** ![RM\_Mentock](https://avatars.discourse-cdn.com/v4/letter/r/e274bd/32.png) [@RM\_Mentock](https://boards.straightdope.com/u/RM_Mentock)\ **Post date:** [September 24, 2000, 3:09am UTC](https://boards.straightdope.com/t/knot-fathom-and-league/34329/2 "2000-09-24T03:09:49Z")
[Freaking tpyos](http://boards.straightdope.com/sdmb/showthread.php?threadid=39430). ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [September 24, 2000, 4:58am UTC](https://boards.straightdope.com/t/knot-fathom-and-league/34329/3 "2000-09-24T04:58:26Z")
Cecil didn’t say-- [Monty did](http://www.straightdope.com/mailbag/mfathom.html). ---
**Author:** ![C\_K\_Dexter\_Haven](https://avatars.discourse-cdn.com/v4/letter/c/b2d939/32.png) [@C\_K\_Dexter\_Haven](https://boards.straightdope.com/u/C_K_Dexter_Haven)\ **Post date:** [September 24, 2000, 11:24am UTC](https://boards.straightdope.com/t/knot-fathom-and-league/34329/4 "2000-09-24T11:24:20Z")
Yep, typo… in process of being fixed (or may be fixed by now.) Sorry 'bout that. ---
**Author:** ![galt](https://avatars.discourse-cdn.com/v4/letter/g/35a633/32.png) [@galt](https://boards.straightdope.com/u/galt)\ **Post date:** [September 24, 2000, 10:08pm UTC](https://boards.straightdope.com/t/knot-fathom-and-league/34329/5 "2000-09-24T22:08:23Z")
Can Monty or anyone else give more specifics about the “log line” with the knots in it, and how that worked? Was it somehow attached to a spring so that the faster the boat went, the more the line was pulled out? How was the device calibrated? Were the knots spaced evenly, or was it a “log line” in more ways than one? 😉 ---
**Author:** ![RM\_Mentock](https://avatars.discourse-cdn.com/v4/letter/r/e274bd/32.png) [@RM\_Mentock](https://boards.straightdope.com/u/RM_Mentock)\ **Post date:** [September 25, 2000, 4:07am UTC](https://boards.straightdope.com/t/knot-fathom-and-league/34329/6 "2000-09-25T04:07:04Z")
It was a knotted rope, knots evenly spaced. When the log was thrown into the water, it stopped dead, relative to the water. So, the speed at which the knots left the boat was your ship’s speed. The corrections due to special relativity were tough, though. ---
**Author:** ![sailor](https://avatars.discourse-cdn.com/v4/letter/s/a587f6/32.png) [@sailor](https://boards.straightdope.com/u/sailor)\ **Post date:** [October 1, 2000, 6:10am UTC](https://boards.straightdope.com/t/knot-fathom-and-league/34329/7 "2000-10-01T06:10:00Z")
This is a page I am working on but the chip log is explained [http://www.geocities.com/alfgon.geo/cninst.htm](http://www.geocities.com/alfgon.geo/cninst.htm) ---
**Author:** ![sailor](https://avatars.discourse-cdn.com/v4/letter/s/a587f6/32.png) [@sailor](https://boards.straightdope.com/u/sailor)\ **Post date:** [October 1, 2000, 6:22am UTC](https://boards.straightdope.com/t/knot-fathom-and-league/34329/8 "2000-10-01T06:22:55Z")
This thread lead me to the mailbag article it refers to and there is a mistake. Because of the shape of the earth, a minute of latitude is not the same length everywhere as it diminishes as you go from the equator to the poles. Length of a degree of latitude: ```auto latitude: meters: 90 1848.9 45 1852.3 0 1855.4 ``` The nautical mile was defined as 1852 m which is a good average value but NOT the value of a minute of latitude at the equator. ---
**Author:** ![RM\_Mentock](https://avatars.discourse-cdn.com/v4/letter/r/e274bd/32.png) [@RM\_Mentock](https://boards.straightdope.com/u/RM_Mentock)\ **Post date:** [October 1, 2000, 12:44pm UTC](https://boards.straightdope.com/t/knot-fathom-and-league/34329/9 "2000-10-01T12:44:40Z")
> [@](#): > > \*Originally posted by sailor \* > **Because of the shape of the earth, a minute of latitude is not the same length everywhere as it diminishes as you go from the equator to the poles.** The length of a minute of latitude _increases_ as you go from the equator to the poles. That was the result that tipped the scales in favor of Newton’s theory of gravitation. [http://www.svanstein.se/maupertuis/data.htm](http://www.svanstein.se/maupertuis/data.htm) This site has some simple diagrams: [http://www.uwgb.edu/dutchs/cosnotes/shapew2.htm](http://www.uwgb.edu/dutchs/cosnotes/shapew2.htm) ---
**Author:** ![sailor](https://avatars.discourse-cdn.com/v4/letter/s/a587f6/32.png) [@sailor](https://boards.straightdope.com/u/sailor)\ **Post date:** [October 1, 2000, 4:32pm UTC](https://boards.straightdope.com/t/knot-fathom-and-league/34329/10 "2000-10-01T16:32:38Z")
RM Mentock, rather than carry on two threads in parallel I will answer in the other thread. ---
**Author:** ![RM\_Mentock](https://avatars.discourse-cdn.com/v4/letter/r/e274bd/32.png) [@RM\_Mentock](https://boards.straightdope.com/u/RM_Mentock)\ **Post date:** [October 2, 2000, 6:37am UTC](https://boards.straightdope.com/t/knot-fathom-and-league/34329/11 "2000-10-02T06:37:03Z")
That other thread is the one that I linked to earlier [http://boards.straightdope.com/sdmb/showthread.php?threadid=39430](http://boards.straightdope.com/sdmb/showthread.php?threadid=39430)