Description and Notes:
This ellipsograph comes in its original card board box, complete with instructions, adoptor for Leroy pens, and advertisement. This appears to be an early example of its kind, as indicated on top of the original box, the patent of which is still pending when it was produced.
Unlike the reletively simple constructed elliptic trammel, which can be used to draw a full ellipse in one pass; this ellipsograph relies on a sophisticated mechanism which, according to the terminology commonly used in the mechanisms literature, is a Stephenson type III linkage with two sliding pairs, to draw a semi-ellipse (it needs to be swung 180 degree to draw the opposite half). Nevertheless, this ellipsograph has the capacity for drawing mathematically true ellipses with the length of the major axis over one feet long.