Jomo,

Regarding your comment of August 5th @ 3:57 p.m. regarding my answer of August 5th @ 3:19 p.m.

‘’The actual explanation about the two different nautical cables is so much simpler: welsh improved is not equal to american custom. The nautical cable is a unit of measure named after the distance of a boat’s cable. Needless to say, the nautical cable as a unit of measurement must be considered to be archaic, and very imprecise. A nautical cable is a section of the boat’s anchor rode(???) and very heavy: you don’t tie knots in it. A logline is a little line tied to a logchip which remains real stationary in the sea as the line runs away and the knots counted for a period of time. I have found two definitions for the nautical cable:
570’
720’
http://www.2-green.com
I don’t know which one of the two defined nautical cables is in common use. Anyway, there is no such thing as one standard nautical cable, and even if there was, it would not be xcole’s 608’ or any where near that length.’’

Jomo, thanks for your carefully calibrated observation.

Oh, by the way, when I spoke to:

Rear Admiral Tim McGee
United States Navy Meteorology & Oceanography Command
National Aeronautics & Space Administration
Stennis Space Center City
Mississippi

He said:

‘’In the United States Navy, 10 nautical cables equal 1 nautical mile, exactly.’’

And:

‘’Despite what some references say, the navy has never used any other length for a nautical cable, certainly not 720’.’’

Info @

http://www.weights-and-measures.com

And topic:

Common Nautical Measure


P.S.
Jomo,
Do you agree with the statement from the Mali Institute of Technology: ‘’Space exploration must be considered archaic, and very imprecise.’’ And have you gone yet for your vacation down at the beach at Timbuctoo?


American Meteorological Society
45 Beacon Street
Boston
Massachusetts
1 ntl.cbl. = 1/10 ntl.ml.

National Center for Atmospheric Research
1850 Table Mesa Drive
Boulder
Colorado
1 ntl.cbl. = 1/10 ntl.ml.

Is McGee from 1824?

When you quote people, you are supposed to leave their words unchanged.

My 1975 edition of American Practical Navigator, still attributed to Bowditch but actually Pub. No. 9 of the Defense Mapping Agency Hydrographic/Topographic Center, defines 1 cable = 720 ft*
(the * is their indicator a conversion is exact. They give no alternative values.)

Seriously, if all your figures are from your ancestor's book, it may have been a useful source at the time, when the US had no office responsible for weights and measures. The first US standardization began in 1832. Most of the values you give are slightly off in terms of modern values. Since you like historical stuff, you might like NIST SP447, a history of US weights and measures. For correct modern values see NIST SP811 or Handbook 44, app. C. All available as free downloads on their website.

<<
And have you gone yet for your vacation down at the beach at Timbuctoo?
>>

I have been to Timbuctoo (early January 1981) and spent a night there en route from Accra to Tunisia by Land Rover. I have a stamp in my now-expired passport to prove it.

<<‘’Despite what some references say, the navy has never used any other length for a nautical cable, certainly not 720’.’’
>>

NIST Handbook 44, Appendix C (page C-14) clearly defines it as
1 cable = 120 fathoms exactly = 720' exactly
Since NIST is in charge of weights and measures for the United States, there you have it. Time to leave 1824 behind.