So drill a hole - eye bolt in - tighten with spanner ? wonder if you can then take them back out ?
I'm thinking they could be used to hang a 'Hammock' under an overhang or between boulders :thinkerg:
Climbers use some things that look like a big nut on a short wire stop, for jamming in nooks and crannies. If they'r good enough to hang a body off, they should be ok with a hammock.
Providing there's x2 nooks/crannies 10' apart at the right height
I can think of quite a few sheltered rocky places that would be hard for tent or tarp
but with a couple of 'bolts' ideal for a hammock set up Danny
yes, abseil down from top to desired poistion, drill hole and insert bolt, there are two types of bolts, one is an ''expanding'' type where you just tighten up with spanner and it expands inside hole to grip rock, the other type is fixed with a resin, and yes the expanding type can be removed with a spanner but the resin type is a permanent fixture. The expanding bolt holds a hanger in place when it's tightened up to fix a carabiner to. A hammock can be slung off these bolts but there are easier ways (which does not damage the rock), there are all sorts of what is called ''protection'' that can be used, ''protection'' is just a name for anything that is stuffed/wedged into a crack which the climber attaches himself too to keep him safe if he falls, nuts/cams/hex's etc are all types of climbing protection to insert into crack, they are of a different size range to cover different size cracks, the climber will carry a range of sizes of protection suitable for particular climbs, these nuts/cams/hex's etc are better for slinging a hammock off as they don't need be drilled into the rock and are just wedged in, however the trouble for hammocking is you might need to carry a range of different sizes to cover different size cracks unless you know beforehand what size you need. Climbers do sleep on hammocks suspended from this type of protection (I have done myself) but bear in mind they will be carrying a range of different sized protection anyway to be used for the actiual climbing itself. Just to add you can use lots of things to stuff in a crack in the rock to hold a hammock, for example before the invention of modern climbing protection ordinary threaded nuts were used (which is why the modern ones are still called nuts even though they look nothing like one). It is even possible to just use knotted rope to hold in a crack, though I would not advise this unless you had a good knowledge of knots and ropework and leverage and breaking strains (shown as KN on climbing ropes/devices). Finally sport climbing has mixed feelings in the climbing fraternity in the Uk because of ethics but that's not relevant here, sport climbers do not need to carry any artificial protection like nuts/cams because that is what those fixed bolts are for.
By the way I loved the photo of the ''U'' shaped tree (pic 20/21), it's amazing how such trees hold on to rock by just their roots, just imagine the leverage that tree is putting on the rock.