Search the Dictionary

The constellation Sextans. Box sextant, a small sextant inclosed in a cylindrical case to make it more portable.

An instrument for taking altitudes, as a quadrant, sextant, etc. Knight.

ed for taking the altitude of the heavenly bodies, but now superseded by the quadrant and sextant; -- so called because the observer turned his back to the body observed.

To mark divisions on; to graduate; as, to divide a sextant.

t formerly used at sea for taking the altitudes of heavenly bodies, now superseded by the sextant; -- called also cross- staff. Brande & C.

l, or a plane reflector adjusted to the true level artificially; -- used chiefly with the sextant for observing the double altitude of a celestial body. -- Celestial horizon. (Astron.) See def. 2, above. -- Dip of the horizon (Astron.), the vertical angle between the sensible horizon and a line to the visible horizon…

. -- Index finger. See Index, 5. -- Index glass, the mirror on the index of a quadrant, sextant, etc. -- Index hand, the pointer or hand of a clock, watch, or other registering machine; a hand that points to something. -- Index of a logarithm (Math.), the integral part of the logarithm, and always one less than the…

method of finding a ship's longitude by comparing the local time of taking (by means of a sextant or circle) a given lunar distance, with the Greenwich time corresponding to the same distance as ascertained from a nautical almanac, the difference of these times being the longitude. -- Lunar month. See Month. -- Lunar…

ining the size or distance of inaccessible objects by means of two reflectors on a common sextant.

instrument and clock; the sun's altitude, or the distance of the moon from a star, with a sextant; the temperature, with a thermometer, etc.

having an arc which measures up to 9Oº, but being itself the eighth part of a circle. Cf. Sextant.

from the smelting furnace. See Pig, 4. -- Pig yoke (Naut.), a nickname for a quadrant or sextant. -- A pig in a poke (that is, bag), a blind bargain; something bought or bargained for, without the quality or the value being known. [Colloq.]

The movable limb of a sextant or other angular instrument. Knight. Radius bar (Math.), a bar pivoted at one end, about which it swings, and having its other end attached to a piece which it causes to move in a circular arc. -- Radius of curvature. See under Curvature.

cting mind. Reflecting circle, an astronomical instrument for measuring angless, like the sextant or Hadley's quadrant, by the reflection of light from two plane mirrors which it carries, and differing from the sextant chiefly in having an entire circle. -- Reflecting galvanometer, a galvanometer in which the deflecti…

A constellation on the equator south of Leo; the Sextant.

short scale made to slide along the divisions of a graduated instrument, as the limb of a sextant, or the scale of a barometer, for indicating parts of divisions. It is so graduated that a certain convenient number of its divisions are just equal to a certain number, either one less or one more, of the divisions of the…