What is "calcium light"

Calcium \Cal"ci*um\ (k[a^]l"s[i^]*[u^]m), n. [NL., from L. calx, calcis, lime; cf F. calcium. See Calx.] (Chem.) An elementary substance; a metal which combined with oxygen forms lime. It is of a pale yellow color, tenacious, and malleable. It is a member of the alkaline earth group of elements. Atomic weight 40. Symbol Ca.

Note: Calcium is widely and abundantly disseminated, as in its compounds calcium carbonate or limestone, calcium sulphate or gypsum, calcium fluoride or fluor spar, calcium phosphate or apatite.

Calcium light, an intense light produced by the incandescence of a stick or ball of lime in the flame of a combination of oxygen and hydrogen gases, or of oxygen and coal gas; -- called also Drummond light and lime light.

Light \Light\ (l[imac]t), n. [OE. light, liht, AS. le['o]ht; akin to OS. lioht, D. & G. licht, OHG. lioht, Goth. liuha[thorn], Icel. lj[=o]s, L. lux light, lucere to shine, Gr. leyko`s white, Skr. ruc to shine. [root]122. Cf. Lucid, Lunar, Luminous, Lynx.]

1. That agent, force, or action in nature by the operation of which upon the organs of sight, objects are rendered visible or luminous.

   Note: Light was regarded formerly as consisting of material particles, or corpuscules, sent off in all directions from luminous bodies, and traversing space, in right lines, with the known velocity of about 186,300 miles per second; but it is now generally understood to consist, not in any actual transmission of particles or substance, but in the propagation of vibrations or undulations in a subtile, elastic medium, or ether, assumed to pervade all space, and to be thus set in vibratory motion by the action of luminous bodies, as the atmosphere is by sonorous bodies. This view of the nature of light is known as the undulatory or wave theory; the other, advocated by Newton (but long since abandoned), as the corpuscular, emission, or Newtonian theory. A more recent theory makes light to consist in electrical oscillations, and is known as the electro-magnetic theory of light.

2. That which furnishes, or is a source of, light, as the sun, a star, a candle, a lighthouse, etc.

   Then he called for a light, and sprang in.
   --Acts xvi. 29.

   And God made two great lights; the greater light to rule the day, and the lesser light to rule the night.
   --Gen. i. 16.

3. The time during which the light of the sun is visible; day; especially, the dawn of day.

   The murderer, rising with the light, killeth the poor and needy.
   --Job xxiv. 1

4. 4. The brightness of the eye or eyes.

   He seemed to find his way without his eyes; For out o'door he went without their helps, And, to the last, bended their light on me.
   --Shak.

5. The medium through which light is admitted, as a window, or window pane; a skylight; in architecture, one of the compartments of a window made by a mullion or mullions.

   There were windows in three rows, and light was against light in three ranks.
   --I Kings vii.4.

6. Life; existence.

   O, spring to light, auspicious Babe, be born !
   --Pope.

7. Open view; a visible state or condition; public observation; publicity.

   The duke yet would have dark deeds darkly answered; he would never bring them to light.
   --Shak.

8. The power of perception by vision.

   My strength faileth me; as for the light of my eyes, it also is gone from me.
   --Ps. xxxviii. 10.

9. That which illumines or makes clear to the mind; mental or spiritual illumination; enlightenment; knowledge; information.

   He shall never know That I had any light of this from thee.
   --Shak.

10. Prosperity; happiness; joy; felicity.

    Then shall thy light break forth as the morning, and thy health shall spring forth speedily.
    --Is. lviii. 8.

11. (Paint.) The manner in which the light strikes upon a picture; that part of a picture which represents those objects upon which the light is supposed to fall; the more illuminated part of a landscape or other scene; -- opposed to shade. Cf. Chiaroscuro.

12. Appearance due to the particular facts and circumstances presented to view; point of view; as, to state things fairly and put them in the right light.

    Frequent consideration of a thing . . . shows it in its several lights and various ways of appearance.
    --South.

13. One who is conspicuous or noteworthy; a model or example; as, the lights of the age or of antiquity.

    Joan of Arc, A light of ancient France.
    --Tennyson.

14. (Pyrotech.) A firework made by filling a case with a substance which burns brilliantly with a white or colored flame; as, a Bengal light.

    Note: Light is used figuratively to denote that which resembles physical light in any respect, as illuminating, benefiting, enlightening, or enlivening mankind.

    Ancient lights (Law), Calcium light, Flash light, etc. See under Ancient, Calcium, etc.

    Light ball (Mil.), a ball of combustible materials, used to afford light; -- sometimes made so as to be fired from a cannon or mortar, or to be carried up by a rocket.

    Light barrel (Mil.), an empty power barrel pierced with holes and filled with shavings soaked in pitch, used to light up a ditch or a breach.

    Light dues (Com.), tolls levied on ships navigating certain waters, for the maintenance of lighthouses.

    Light iron, a candlestick. [Obs.]

    Light keeper, a person appointed to take care of a lighthouse or light-ship.

    Light money, charges laid by government on shipping entering a port, for the maintenance of lighthouses and light-ships.

    The light of the countenance, favor; kindness; smiles.

    Lord, lift thou up the light of thy countenance upon us.
    --Ps. iv. 6.

    Northern lights. See Aurora borealis, under Aurora.

    To bring to light, to cause to be disclosed.

    To come to light, to be disclosed.

    To see the light, to come into the light; hence, to come into the world or into public notice; as, his book never saw the light.

    To stand in one's own light, to take a position which is injurious to one's own interest.

n. limelight

n. a lamp consisting of a flame directed at a cylinder of lime with a lens to concentrate the light; formerly used for stage lighting [syn: limelight]