Garth asked: "One of my bikes has the modern brakes that are now called dual pivot because the right arm pivots on the center bolt and the left pivots on its own side bolt. Well this is a good modern idea, but it seems still quite a bit less simple and elegant than the old center pull system which gives you two side pivots and a symmetrical arrangement to boot. The question is, did any manufacturer ever come up with a centerpull arrangement that had integral in the design its own pulling point, so that nothing needed to be attached to the headset nor the rear seatpost bolt? A quick search of my memory nor books I have turned up anything. Such a device could extend up from the center bolt the same one or two inches the common centerpull arrangement now has."
Like virtually all things found on bikes, these are all very old ideas. I would guess that the idea dates from the early 1900's. Quite a few people have already mentioned British designs from the 30's and 40's. You can see a few examples of Italian ones from the 40's here:
http://www.wooljersey.com/
These ones are marked Brevettato on the back of them meaning that they were patented.
Another set that are actually quadruple pivots can be seen here:
http://www.wooljersey.com/
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Steven Maasland
Moorestown, NJ, USA