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cordage

cordage

Ropewasoneofman'sfirstinventions,certainlypredatingthe

wheel,anditsstructurehasremainedessentiallythesamefor
centuries,althoughtheadventofsyntheticfibershasgivenit a
strengthcomparable,andincertainwayssuperior,tothatof

steel.
Ropeandknotaretwowordsthatgohandinhand,forone

isuselesswithouttheother;whatuse isa lengthofrope
withoutatleastoneknotinit?Uptoafewdecadesago,the

choiceofropewaslimited:hempandmanillawereusedfor

their strength, cotton for manageability, and sisal for
economy; buttodaytheavailabilityofsyntheticfibershas

produceda specializedtypeofropeforeveryapplication,

structure

Ropeismadeupoffibers(a)twistedtogethera numberof

times,eachintheoppositedirectiontothepreviousone,to

form,firstofall,theyarn(b).thenthestrands(c)andfinally

therope itself,This operation isknown aslaying upand

producestheclassicropegenerallymadeupofthree(1)and

sometimes morestrands (2),but thereisanotherway of

producingrope,namelybybraidingtheyarn (3)insteadof

twistingit together; withthiskind ofropethe outerpart,

knownasthesheath(e),isbotha protectiveandanattractive

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