While hunting around for more background on Taguel’s mould-breaking elliptical compass, I came across a long and detailed paper entitled “Elliptographs, and the Application of Elliptical Curves” by Frank J. Gray, published in the Journal of the Society of Arts, January 17, 1902. Of particular interest in the context of Taguel’s design is the illustration of an instrument patented in 1862 by Alfred Joseph Hale of Clerkenwell, London, reproduced as Fig. 6 in the article. It works on a similar principle to Taguel’s, equipped with a spring-loaded arm that rotates around an elliptical template, but does not seem to have been particularly popular at the time, at least according to the author:
Ellipse compasses have been devised, but they have not found favour on account of the inconvenience of using them. They have elliptical templets [sic.], affixed in a horizontal position to the central leg of the compasses, for the purposes of limiting the amount of curvature to be traced by the describing leg. The instrument patented by Alfred Joseph Hale, Clerkenwell, in 1862 (Fig. 6) is on this principle. Another device of this class is the triangular compasses with a pencil-holder which slides up and down one of the legs set at an angle with the drawing surface. The pencil marks from different faces of its point as it traces the curve; therefore a drawing pen cannot be used with this method. These ellipse compasses, like those of similar size for circles, are intended only for small figures.
The second device described is clearly of the type now best known by Haff’s “whale tail” elliptical compass. At the time of the paper, a triangular compass-based version of this was manufactured by WF Stanley, although I have never seen an actual specimen of one. It would be an interesting project to trace the origins of both types of elliptical compass through production models rather than just the documentary evidence. In the meantime, I will keep looking for more information on Taguel, now it is clear that he was indeed the inventor of the Baraban-made instrument.
