The "analog gadget" you describe for drawing circles or ellipses is often made as a folk toy with the axis points on wood blocks sliding in a pair of grooves at right angles in a larger block. I have two of these, one in painted wood with the grooves formed by gluing blocks together and the other in walnut with the grooves cut in a solid block. The painted one has the words "NING Y NING" painted on it. What I am curious about is - what is the name of this device as a folk/craft toy? I have one of David Wells' books that refers to it as a "trammel" and says such devices were made commercially for drawing ellipses, but gives no sources. The diagram in the book shows that it is in fact the same device. But trammel is a vague general word that applies to several gizmos - what was the toy called by its makers? Wells also refers to an "ellipsograph", but doesn't say if it's the same thing.

Thanks, Cuyler Brooks

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