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On Fri, 18 Jul 2008 07:11:31 -0400, Eisboch wrote:




Please explain. Last time I checked a "Knot" multiplied by 1.8
something, something, something equalled one kilometer per hour.

That's a knot ..... coverted to a metric unit.

What's the origin of a "knot"?

Eisboch


Apparently, knots and meters are tied together, somewhat. A nautical
mile is a minute of latitude. A meter is 1/10,000,000 of the distance
from the equator to the North Pole, and, obviously, a knot is a nautical
mile per hour. Thank you, wikipedia.


They are tied together apparently, but by coincidence, not mathematical
design or part of the Metric system.
Quoting Wikipedia:

Origin
Until the mid-19th century vessel speed at sea was measured using a chip
log. This consisted of a wooden panel, weighted on one edge to float upright
and thus have substantial water resistance, attached by line to a reel. The
chip log was "cast" over the stern of the moving vessel and the line allowed
to pay out. Knots placed at a distance of 47 feet 3 inches (14.4018 m)
passed through a sailor's fingers, while another sailor used a 30 second
sandglass (28 second sandglass is the current accepted timing) to time the
operation.[6] The knot count would be reported and used in the sailing
master's dead reckoning and navigation. This method gives a value for the
knot of 20.25 in/s, or 1.85166 km·h?1. The difference from the modern
definition is less than 0.02%.


[edit] Modern use
Although the unit "knots" does not fit within the primary SI system, its
retention for nautical and aviation use is important for navigational
reasons, since the length of a nautical mile is almost identical to a minute
of latitude. As a result, distance in nautical miles on a navigational chart
can easily be measured by using dividers and the latitude indicators on the
side of the chart.

Nautical speed is sometimes erroneously expressed as "knots per hour" which
would actually be a measure of acceleration, as in "nautical miles per hour
per hour."



Eisboch