En route to the British Museum, I stopped off to visit a friend who lives near Sheffield. I met Andy and Elaine a few years back. Elaine really wanted to know more about sprang. They were, at that time preparing to participate in an event, re-doing the battle of Marathon in Greece ... he was going to be one of the bad guys. I made him a pair of leggings, appropriate to the time period, and based on research by Dagmar Drinkler.
It seems that Andy has worn these leggings to several events. Imagine my surprise when I read on the internet that sprang is not at all suitable for leggings! Andy showed me a post indicating that, with one broken thread, the pants will fall apart. This, I thought, is the perfect moment for a bit of testing, some experimental archaeological if you will.
Andy allowed me to cut a thread in his leggings. To make it a fair test, I cut a thread at the knee, a place that would be affected by movement of the leg.
Andy took a picture of me cutting the thread just in front of his left knee.
Here you see the broken thread at the left knee.
Andy then went outside to do some work in the yard.
He cleared his deck of the leaves, and tended to his leaf-blowing machine.
His leggings stayed on the entire time ... no falling apart ... no falling off. Indeed no increase in the size of the hole. The wool threads stayed put.
Wool has a certain 'grabbiness' to it's surface, and the wool sock-yarn that I had used to make the leggings is no exception.
Yes, I've seen silk sashes in museum collections with long vertical slits, where a thread broke. The slipperiness of silk as well as the simple interlinking structure would allow a slit to develop ... but the slit will only open up so far. At some point the length of the cut threads will, itself, prevent further un-doing. The structure of the zig-zag pattern in these leggings also helps prevent un-doing.
I repaired the damage I had caused, tied a knot to mend the cut ends, and tucked the knot to the inside of the leggings.
The damage is now repaired, the knot almost imperceptible.
A big Thank You to Andy Cropper for permitting me to carry out this test.