Obsessing about rope

Scott Bradner

 

An earlier version of this article was published in the April 2020 issue of the USSCMSG Broadside.

 

Many years ago, long enough ago that I do not remember who, where, why or when, someone told me that the lower ropes on clipper ships were left twisted whereas the running rope and much of the other rope was right twisted.  Since this was long before I was involved in ship modeling, I am puzzled as to what the context might have been for someone to tell me that.  In any case, that factoid stuck with me in the background through the years and popped to the foreground when I started work on a model of the Donald McKay clipper ship Flying Cloud and it set me on a quest to find out just what the story was.  This article is the result of that quest.

 

First of all, rope is far from a new concept. Figure 1 is of a coil of rope from about 3,800 years ago that was found in an Egyptian cave.  This rope was likely made for rigging Egyptian river boats.  It looks just like the rope we use today.

 

 

 

 

Figure 1

 

But, let’s start out with a review about the types of rope used on ships back in the day (where “the day” was anywhere from 150 years ago to a thousand years ago).  For thousands of years rope has basically been plant material twisted into yarns, and those yarns twisted into rope.  For most of this time there have been three basic rope designs known (at least in the 1800s) as “hawser-laid,” “cable-laid,” and “shroud-laid.” See figure 2.

 

 

Figure 2

 

Thus, hawser-laid rope starts with multiple thin fibers which are twisted together into yarns.  Three yarns, in turn, are then twisted together to produce a rope.  Note that the direction of twist reverse at each stage.  So, if you twist the fibers together in a clockwise direction to produce the yarn, you would twist the yarns together in a counter clockwise direction to make the rope.  You need to do this so that the tensions in the rope try to hold the rope together rather than just let it unravel.

 

Three hawser-laid ropes can be twisted together to produce a cable-laid rope.

 

Finally, four hawser-laid ropes can be twisted together to produce a shroud-laid rope but when you do that you wind up with a void in the middle of the rope so you normally have to fill that void with yet another hawser-laid rope.

 

Now a word about the handedness of rope.  Ropes can have a right or left twist, see figure 3.

Figure 3

 

Most rope on ships and for other uses has a right twist.  The 3,800 year old Egyptian rope in figure 1 has a right twist, as would the rope you buy at the hardware store tomorrow.  That means that both cable- and shroud-laid rope would normally have a left twist.  That said, it turns out that some hawser-laid rope used on both warships and clipper ships had a left twist.  If you have hawser-laid rope with a left twist you could make cable- and shroud-laid rope with a right twist if you wanted to.  The big question is “what rope was used for what purpose on these ships and why chose that particular rope?”

 

A lot of the rope on sailing ships was, and is, running rigging that goes through blocks and needs to be flexible.  Historically, almost all running rope was hawser-laid rope with a right twist.  Apparently, this was because such role was strong enough and flexible enough to do the job and last a reasonable length of time.  I say “apparently” because I have not found any document that says why hawser-laid rope with a right twist was chosen for running rigging but I did find a few references that said that specific ropes, for example cannon breaching rope,[1] and the rope used for some upper yard braces on clipper ships[2] were hawser-laid rope with a left twist because, it was claimed, such rope was softer and easier to handle, but was not as durable.

 

That leaves the standing rigging.  Standing rigging on old sailing ships could be very large.  See the figure below for an example, figure 4 shows a piece of either an anchor rope or of a shroud from the Mary Rose that sank in 1514.

 

 

Figure 4

 

Figure 4 shows a cable-laid rope with a left twist.  When I finally found documentation that talked about the types of rope used on big sailing ships, the documentation said that the shrouds, stays and backstays of large sailing merchant and warships was cable-laid.[3]   But by the mid 1850s a switch was underway to shroud-laid or hawser-laid.[4]  The figure below shows a shroud and deadeye from the HMS Invincible which sank in 1758.  The rope is cable laid with a left twist. Standing rigging was also soaked with Stockholm Tar[5] to improve its water resistance.

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Figure 5

 

But why would they decide to use cable-laid rope for the shrouds, stays and backstays on big sailing ships?  The few old documents that discuss the use of cable-laid rope point out that cable-laid rope is weaker than hawser-laid but it seems that the mariners of old thought that cable-laid rope was watertight.  For example, see this quote from Luce’s 1863 Seamanship:

Cable-laid Rope, , is left handed rope of nine strands and is so made to render it impervious to water, but the additional twist necessary to lay it up seems to detract from the strength of the fibre, the strength of plain laid being to that of cable-laid as 8.7 to 6; besides this, it stretches considerably under strain.

It may or not have been the case that cable-laid rope was more “impervious to water” than hawser-laid rope but the fact that it was a widely assumed feature would lead shipbuilders to use cable-laid rope where they did not want to have to replace it often.  The logic seems to have been: if using cable-laid rope kept the water out maybe the rope would rot less and thus last longer.

 

One of the things that made the start of this quest harder was that the most common sources of information about the rigging of large sailing ships, Biddlecombe’s The Art of Rigging, and Underhill’s Masting and Rigging the Clipper Ship and Ocean Carrier, do not mention the types of rope used to rig the ships. There were tidbits of information scattered about in documents such as Luce’s 1884 Textbook of Seamanship, but the information was hard to find. I did track down a resource that provided much more information:  Peter Force’s Tables (it has a very long name that starts with “Tables”). I have posted a copy of the Force book on my website. The Force book lists all ropes that were needed on a large sailing vessel and specifically notes which of the ropes are cabled.  After publishing the first version of this article I found that early editions of the Art of Rigging, for example the one published by David Steel in 1800, also show which ropes are cabled.  Both of these references indicate that most of the standing rigging on sailing ships up until 1860 or so was cable-laid, including the stays, shrouds and back stays.

 

After all the research, I decided to use natural color hawser-laid rope with a right twist for all of the running rigging except for a few yard braces. I also decided to use dark brown/black cable-laid rope for the shrouds, stays and backstays and brown/black hawser-laid rope with a right twist for the rest of the standing rigging.

 

photo credits:

figure 1: https://www.bu.edu/cas/magazine/fall10/Egypt/index.shtml

figure 4: https://twitter.com/MaryRoseLearn/status/895933054803378176

figure 5: unknown source

 

 

 

 

 



[1] Burney The Boy’s Manual of Seamanship & Gunnery 1871 page 127

[2] Luce Textbook of Seamanship 1884 pages 139-140

[3] Steel-1880 The Art of Rigging page 61 & 88, Anderson Rigging of Ships in the Days of the Sprit Topmast 1927 page 84, Luce Textbook of Seamanship 1884 page 23, Force, Tables 1826 page 15

[4] Lever The Young Sea Officer’s Sheet Anchor - 1853

[5] Stockholm Tar is brownish-black in color, not pure black as is often used on ship models.