VIII. He beareth Argent, a Pair of Compasses, Sable. This is born by the name of Compashale.
A. a Cheveron engrailed between 3 Compasses S. is the Coat Armour belonging to the Company of Carpenters; the same is born in the Joyners and Masons Arms.
→ Some Blazon them Compasses dilated, or opened; but that term needs not; because in Coats of Arms, they are ever one of three parts, or thereabouts, opened to their extention.
The Joynt is the place where the Compasses move and turn.
The Cheeks of the Joynt, is where they go in one to the other.
The Shanks, The Points.
IX. He beareth Gules, a Pair of Sliding or Circle Dividers, Or. These are Compasses which open upon a Brass semi-circle, and by a small Screw is made fast at any station.
B. 3 such O. pointed S. is born by Bonny.
G. one pair of such O. born by Bartten.
X. He beareth Gules, a Pair of Screw Dividers, Or; Pointed, Sable. Born by Distance. These are Compasses opened and shut with a screw, so that there is noe danger of their moveing from their station. By all these foresaid Compasses, are described Circles Ovals &c. and also Distances are measured and set off from the Rule, or from any other divided Rod or Staffe, to the thing to be wrought upon.
V. a paire of Dividers A. born by Port.
A, 3 such S. born by Dividend.
XI. He beareth Or, a Paire of Callippers, Sable born by Dimmiter. As common Compasses are for measuring Distances upon a plain Superficies; so the Callippers measure the distance or Thickness of any Cilindrick or Orbicall body, either in their extremity, or any part lesse then the extremity. So that the just Diameter is known by the distance of the points of the Compasse, be the same either Feet or Inches.
A. 3 such S. born by Scalpper.
XII. He beareth Sable, a Joyners Bevil Square, Or. Born by Bevill. of this kind of bearing in Arms, see more lib. 1. chap. 9. numb. 78.
B. 3 such O. is born by Ressen.
In the base of this square is a Pair of Callippers with their Points Crossing one another, Sable; in a field Argent. is born by Van Slogan.
— From Randle Holme’s “The Academy of Armory, or, A Storehouse of Armory and Blazon” Book III, Chapter IX. Why am I reading this?