What is "globe sight"

Globe \Globe\ (gl[=o]b), n. [L. globus, perh. akin to L. glomus a ball of yarn, and E. clump, golf: cf. F. globe.]

1. A round or spherical body, solid or hollow; a body whose surface is in every part equidistant from the center; a ball; a sphere.

2. Anything which is nearly spherical or globular in shape; as, the globe of the eye; the globe of a lamp.

3. The earth; the terraqueous ball; -- usually preceded by the definite article.
   --Locke.

4. A round model of the world; a spherical representation of the earth or heavens; as, a terrestrial or celestial globe; -- called also artificial globe.

5. A body of troops, or of men or animals, drawn up in a circle; -- a military formation used by the Romans, answering to the modern infantry square. Him round A globe of fiery seraphim inclosed. --Milton. Globe amaranth (Bot.), a plant of the genus Gomphrena ( G. globosa), bearing round heads of variously colored flowers, which long retain color when gathered. Globe animalcule, a small, globular, locomotive organism ( Volvox globator), once throught to be an animal, afterward supposed to be a colony of microscopic alg[ae]. Globe of compression (Mil.), a kind of mine producing a wide crater; -- called also overcharged mine. Globe daisy (Bot.), a plant or flower of the genus Globularing, common in Europe. The flowers are minute and form globular heads. Globe sight, a form of front sight placed on target rifles. Globe slater (Zo["o]l.), an isopod crustacean of the genus Spheroma. Globe thistle (Bot.), a thistlelike plant with the flowers in large globular heads ( Cynara Scolymus); also, certain species of the related genus Echinops. Globe valve.

   1. A ball valve.

   2. A valve inclosed in a globular chamber.
      --Knight.

      Syn: Globe, Sphere, Orb, Ball.

      Usage: Globe denotes a round, and usually a solid body; sphere is the term applied in astronomy to such a body, or to the concentric spheres or orbs of the old astronomers; orb is used, especially in poetry, for globe or sphere, and also for the pathway of a heavenly body; ball is applied to the heavenly bodies concieved of as impelled through space.

A globe sight is a front sight component used to assist the aiming of a gun/device, usually those intended to launch projectiles, such as firearms, airguns, and crossbows. It is found in particular as a front sight element on rifles.

To obtain a usable sighting line the diopter has to have a complementing rear sight element.

Diopter and globe sighting lines are commonly used in ISSF match rifle shooting events.