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It is not only important, but, in a degree necessary, that the people of this country, should have an American Dictionary of the English language; for, although the body of the language is the same as in England, and it is desirable to perpetuate that sameness, yet some differences must exist. Language is the expression of ideas; and if the people of one country cannot preserve an identity of ideas, they cannot retain an identity of language. |
SECT'OR, n. [L. seco, to cut.]
1. In geometry, a part of a circle comprehended between two radii and the arch; or a mixed triangle, formed by two radii and the arch of a circle.
2. A mathematical instrument so marked with lines of sines, tangents, secants, chords, &c. as to fit all radii and scales, and useful in finding the proportion between quantities of the same kind. The sector is founded on the fourth proposition of the sixth book of Euclid, where it is proved that similar triangles have their homologous sides proportional.
A part of a
circle comprehended between two radii and the included arc.
A mathematical instrument, consisting of
two rulers connected at one end by a joint, each arm marked with
several scales, as of equal parts, chords, sines, tangents, etc., one
scale of each kind on each arm, and all on lines radiating from the
common center of motion. The sector is used for plotting, etc., to any
scale.
An astronomical instrument, the limb of
which embraces a small portion only of a circle, used for measuring
differences of declination too great for the compass of a micrometer.
When it is used for measuring zenith distances of stars, it is called
a zenith sector.
Dip sector, an instrument used for measuring the dip of the horizon. -- Sector of a sphere, or Spherical sector, the solid generated by the revolution of the sector of a circle about one of its radii, or, more rarely, about any straight line drawn in the plane of the sector through its vertex. | ||||||||