Double hinged Darby Leg irons

I'm curious to know how many of these exist. I'm pretty sure John Bushey had one and a photo of a Hiatt display also had one.
I suspect they were experimental in nature and were not worth continuing. Obviously making the extra hinge was more work and there is more movement of the bow. The extra 'play' in the bow means the alignment did not need to be perfect to engage the lock, but would that also make them easier to break because they were less rigid? The lock tube is cast I believe, and everything else is blacksmith made. The lock tubes are very short and use a short handcuff width key. I have found that early leg irons use handcuff size keys. All hinges are folded straps and the clevis pierces a strap also holding it together. There are no stampings on them at all and the finish makes me think they are quite early. Can anyone add anything more about these leg irons? Paul

The first pair of these I saw belonged to Chris Gower. From memory the cuff was not a blacksmithed. The lock appeared to be the same length as would have been used on a handcuff. We discussed the likelihood that the double hinge would compensate for the shorter (shorter than required for a non adjustable leg iron) lock tube, and that a handcuff length lock would be used for both.

I think the double hinge like the multiply links for the  'flexible' model make locking that cuffs more difficult. Having single hinge means a fixed point for the hinge and that the bow will automatic align to the lock when closed.

It may have something to do with the economics of melting the steel required to do a pour of castings. More, smaller locks could be produced from the same size crucible than larger one. The double hinge have would be the answer to the  cuff opening enough to go around an ankle.

"The double hinge have would be the answer to the cuff opening enough to go around an ankle."

You are absolutely right Ian. When I close them, the opening for a solid bow would be too small to apply them. 
Shown here beside an average size pair of cuffs, you can see the scale.
Paul

Amazing!

I believe the one Chris Gower owned, had a lock almost as long as a regular cuff. Your example is quite a bit shorter. Quite unique.

I have had two interesting Double Hinge Legirons over the past 50 years. The one I really liked I traded with Tom Gross when he visited me about 20 years ago.
I think it is illustrated in Alex Nichols book, we are away for a few days when I get back I will find photos.

Photo attached showing the double hinge Legirons that I traded with Tom Gross. As you can see the barrel is a normal size Darby Handcuff. I am still looking for the photo of the other set I had which had a round bar linkage to extend their size,