A Knotty Problem

One of the most confusing concepts for a new sailor is the “knot.” Sure, we all know what knots are. They are what you tie in your shoe laces, or what you use to tie the rowboat onto the roof of your car. But “knot” is also used as a nautical measure of speed. Confused? Don’t be. We’re here to untangle the issue for you.

Knots, bends, and hitches.

First, let’s consider the kind of knots you tie. There are of course many different kinds of knots that are used aboard a boat, but they’re not technically all “knots.” That’s right, the thousands of different kinds of ways to tie the ends of a line together, to fasten a line to something (like a spar or a cleat), or to tie one line to another, are classified differently. They are known as knots, bends, and hitches, and the name tells you how they should be used.

There are eight different knots, bends, and hitches that every boater needs to know, and every boater will find among them the ones that are most used on their boat.

Reef knot

Used to tie the two ends of a line together. The specific use of this knot on a sailboat is to tie a reef into a sail.

It is tied by holding the two ends of the line and following the sequence:

“left over right and under, right over left and under”

530503_77482454 reef knot

example of a reef knot photo courtesy of marcin krawczyk

 

Bowline knot

Used to tie a temporary loop into a line. This has many uses, such as securing sheets to a jib sail.

When tied correctly, the end will be inside the loop of the knot.

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Figure of eight knot

Sometimes called a stopper knot, this knot is often tied into the end of a sheet to prevent it pulling through a block or fairlead.

387965_7795 figure of eight knot

example of a figure of eight knot photo courtesy of marcin krawczyk

 

Sheet bend

Used to join two lines. If the lines are of different thickness, the thinner line is tied to a loop in the larger line. For security, a double sheet bend can be tied by bringing the end of the smaller line around the back of the loop and under the locking turn, parallel with the first turn.

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Clove hitch

Used to secure a line to a spar or a fitting. This hitch is often used to secure fenders to the lifelines.

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Round turn and two half hitches

As the name suggests, the line is passed around a spar or a fitting and secured with two hitches.

P1080333

 

Cleat hitch

Used to secure a sheet or a line to a cleat.

P1080329

 

Rolling hitch

Used to secure a line to a spar to withstand a horizontal pull in one direction only.

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829186_22798158 a cut splice in a line

example of a cut splice photo courtesy of Andy Hargraves

A splice is a whole different thing. You can use a long splice or a short splice to permanently join the ends of two lines. You can use a splice to make a permanent loop in the bight of a line or at the end of it. And you can splice a line to a chain for a an anchor rode, or even splice the ends of a short piece of line together to make a grommet.

 

 

But what about knots of speed?

chronometer photo courtesy of Antonio Jiménez Alonso

chronometer
photo courtesy of Antonio Jiménez Alonso

It has always been important for a mariner to know how fast a boat was going in order to navigate. Long before GPS and digital charts, and even before the development of a reliable seagoing chronometer, sailors had to navigate by “deduced reckoning”, simplified as dead reckoning.

They did that by determining their speed and bearing, and then plotting those on a chart. The constant routine of turning the hourglass to keep track of time, and periodically checking their speed gave them a remarkably good estimate of their location.

So how did they calculate their speed?

Old time sailors used a panel of wood (the “log”), weighted on one side to float vertically, tied to a line into which knots were tied at equal intervals. The log was tossed over the side, and the sailor counted the number of knots that passed between his fingers as the log floated towards the stern. The number of knots that passed in a given time was the speed the boat was traveling.

photo courtesy of Ove Tøpfer

photo courtesy of Ove Tøpfer

Nautical speed is measured in nautical miles per hour. Early cartographers determined the length of a nautical mile from the circumference of the earth, one mile being one minute of latitude measured along a meridian.

Knots are still used today to express wind speed and boat speed, as well as to classify sea conditions.

But that is a story for another blog.

References:Burgess’s Knots, Ties & Splices, Revised by Crab Searl, Routledge & Kegan Paul, 1980
The Marlinspike Sailor, Hervey Garrett Smith, John de Graff, Inc, 1981
The New Glenans Sailing Manual, translation by James MacGibbon, R. R. Donnelly & Sons, 1978
 
Feature image courtesy of John Byer.
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