Patent # 3,143,807
Pendulum Drawing Device; G. L. Christie, 1964
An original but overly complex arraignment of pulleys, strings and counter weights. With so many moving parts introducing friction into the system, how do the pendulums maintain their periodic motion for any length of time? This design is clearly a violation of the K.I.S.S. principle - Keep It Simple, Stupid!
Note the addition of a third pendulum in the drawing on page two. Although this is very clever concept, I would be surprised it this thing could ever be made to work right.
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