What is "elliptic compasses"

Elliptic \El*lip"tic\, Elliptical \El*lip"tic*al\, a. [Gr. ?: cf. F. elliptique. See Ellipsis.]

1. Of or pertaining to an ellipse; having the form of an ellipse; oblong, with rounded ends.

   The planets move in elliptic orbits.
   --Cheyne.

   The billiard sharp who any one catches, His doom's extremely hard He's made to dwell In a dungeon cell On a spot that's always barred. And there he plays extravagant matches In fitless finger-stalls On a cloth untrue With a twisted cue And elliptical billiard balls!
   --Gilbert and Sullivan (The Mikado: The More Humane Mikado Song)

2. Having a part omitted; as, an elliptical phrase.

3. leaving out information essential to comprehension; so concise as to be difficult to understand; obscure or ambiguous; -- of speech or writing; as, an elliptical comment.

   Elliptic chuck. See under Chuck.

   Elliptic compasses, an instrument arranged for drawing ellipses.

   Elliptic function. (Math.) See Function.

   Elliptic integral. (Math.) See Integral.

   Elliptic polarization. See under Polarization.