horizon glass
11Navigation — This article is about determination of position and direction on or above the surface of the earth. For other uses, see Navigation (disambiguation). Table of geography, hydrography, and navigation, from the 1728 Cyclopaedia. Navigation is the… …
12Sextant — This article is about the sextant as used for navigation. For the astronomer s sextant, see Sextant (astronomical). : For the history and development of the sextant see Reflecting instruments A sextant is an instrument generally used to measure… …
13Gunner's quadrant — Quadrant Quad rant, n. [L. quadrans, antis, a fourth part, a fourth of a whole, fr. quattuor four: cf. F. quadrant, cadran. See {Four}, and cf. {Cadrans}.] 1. The fourth part; the quarter. [Obs.] Sir T. Browne. [1913 Webster] 2. (Geom.) The… …
14Gunter's quadrant — Quadrant Quad rant, n. [L. quadrans, antis, a fourth part, a fourth of a whole, fr. quattuor four: cf. F. quadrant, cadran. See {Four}, and cf. {Cadrans}.] 1. The fourth part; the quarter. [Obs.] Sir T. Browne. [1913 Webster] 2. (Geom.) The… …
15Hadley's quadrant — Quadrant Quad rant, n. [L. quadrans, antis, a fourth part, a fourth of a whole, fr. quattuor four: cf. F. quadrant, cadran. See {Four}, and cf. {Cadrans}.] 1. The fourth part; the quarter. [Obs.] Sir T. Browne. [1913 Webster] 2. (Geom.) The… …
16Quadrant — Quad rant, n. [L. quadrans, antis, a fourth part, a fourth of a whole, fr. quattuor four: cf. F. quadrant, cadran. See {Four}, and cf. {Cadrans}.] 1. The fourth part; the quarter. [Obs.] Sir T. Browne. [1913 Webster] 2. (Geom.) The quarter of a… …
17Quadrant of altitude — Quadrant Quad rant, n. [L. quadrans, antis, a fourth part, a fourth of a whole, fr. quattuor four: cf. F. quadrant, cadran. See {Four}, and cf. {Cadrans}.] 1. The fourth part; the quarter. [Obs.] Sir T. Browne. [1913 Webster] 2. (Geom.) The… …
18mirror sextant — mirror sextant, the common sextant having a horizon glass and an index glass …
19Octant (instrument) — Octant. This instrument, labelled Crichton London, Sold by J Berry, Aberdeen, appears to have an ebony frame with ivory scale, vernier and signature plate. The index arm and mirror supports are brass. Rather than use a sighting telescope, this… …
20Rainbow — For other uses, see Rainbow (disambiguation). Double rainbow and supernumerary rainbows on the inside of the primary arc. The shadow of the photographer s head on the bottom marks the centre of the rainbow circle (antisolar point). A rainbow is… …
