Emily Dickinson Lexicon

COM'PASS, n. [Fr. compas; Sp. compas; It. compasso; Port. compasso; con or com and Fr. pas, Sp. paso, It. passo, a pace or step, L. passus, which coincides with the participle of pando, to open or stretch. See Pace and Pass. A compass is a stepping together. So in Spanish and Portuguese, it signifies a beating of time in music.]

1. Stretch; reach; extent; the limit or boundary of a space, and the space included; applied to time, space, sound, &c. Our knowledge lies within a very narrow compass. The universe extends beyond the compass of our thoughts. So we say, the compass of a year, the compass of an empire, the compass of reason, the compass of the voice. And in that compass all the world contains. – Dryden.
2. A passing round; a circular course; a circuit. Time is come round; / And where I did begin, there shall I end: / My life has run its compass. Shak. They fetched a compass of seven days journey. – 2 Kings iii. 2 Sam. v. Acts xxviii.
3. Moderate bounds; limits of truth; moderation; due limits. In two hundred years, (I speak within compass,) no such commission had been executed. – Davies. This sense is the same as the first, and the peculiar force of the phrase lies in the word within.
4. The extent or limit of the voice, or of sound. [See No. 1.]
5. An instrument for directing or ascertaining the course of ships at sea, consisting of a circular box, containing a paper card marked with the thirty-two points of direction, fixed on a magnetic needle, that always points to the north, the variation excepted. The needle with the card turns on a pin in the center of the box. In the center of the needle is fixed a brass conical socket or cap, by which the card hanging on the pin turns freely round the center. The box is covered with glass, to prevent the motion of the card from being disturbed by the wind. – Encyc.
6. Compass or Compasses, [or a pair of compasses, so named from its legs, but pair is superfluous or improper, and the singular number, compass, is the preferable name,] an instrument for describing circles, measuring figures, &c., consisting of two pointed legs or branches, made of iron, steel or brass, joined at the top by a rivet, on which they move. There are also compasses of three legs or triangular compasses, cylindrical and spherical compasses, with four branches, and various other kinds. – Encyc.
7. An instrument used in surveying land, constructed in the main like the mariner's compass; but with this difference, that the needle is not fitted into the card, moving with it, but plays alone; the card being drawn on the bottom of the box, and a circle divided into 360 degrees on the limb. This instrument is used in surveying land, and in directing travellers in a desert or forest, miners, &c. – Encyc.