* 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.

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.

The murderer, rising with the light, killeth the poor and needy. Job xxiv. 14.

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.

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

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

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

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

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

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

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

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

* 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 powder 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.

If a thousand candles be all lighted from one. Hakewill.

And the largest lamp is lit. Macaulay.

Absence might cure it, or a second mistress
Light up another flame, and put out this. Addison.

Ah, hopeless, lasting flames ! like those that burn
To light the dead. Pope.

One hundred years ago, to have lit this theater as brilliantly as it is now lighted would have cost, I suppose, fifty pounds. F. Harrison.

The sun has set, and Vesper, to supply
His absent beams, has lighted up the sky. Dryden.

His bishops lead him forth, and light him on. Landor.

To light a fire, to kindle the material of a fire.

These weights did not exert their natural gravity, . . . insomuch that I could not guess which was light or heavy whilst I held them in my hand. Addison.

Ye shall find rest unto your souls. For my yoke is easy, and my burden is light. Matt. xi. 29, 30.

Light sufferings give us leisure to complain. Dryden.

Unmarried men are best friends, best masters . . . but not always best subjects, for they are light to run away. Bacon.

There is no greater argument of a light and inconsiderate person than profanely to scoff at religion. Tillotson.

Seneca can not be too heavy, nor Plautus too light. Shak.

Specimens of New England humor laboriously light and lamentably mirthful. Hawthorne.

Are his wits safe? Is he not light of brain ? Shak.

To a fair semblance doth light faith annex. Spenser.

A light wife doth make a heavy husband. Shak.

Light cavalry, Light horse (Mil.), light-armed soldiers mounted on strong and active horses. -- Light eater, one who eats but little. -- Light infantry, infantry soldiers selected and trained for rapid evolutions. -- Light of foot. (a) Having a light step. (b) Fleet. -- Light of heart, gay, cheerful. -- Light oil (Chem.), the oily product, lighter than water, forming the chief part of the first distillate of coal tar, and consisting largely of benzene and toluene. -- Light sails (Naut.), all the sails above the topsails, with, also, the studding sails and flying jib. Dana. -- Light sleeper, one easily wakened. -- Light weight, a prize fighter, boxer, wrestler, or jockey, who is below a standard medium weight. Cf. Feather weight, under Feather. [Cant] -- To make light of, to treat as of little consequence; to slight; to disregard. -- To set light by, to undervalue; to slight; to treat as of no importance; to despise.

From his head the heavy burgonet did light. Spenser.

When she saw Isaac, she lighted off the camel. Gen. xxiv. 64.

Slowly rode across a withered heath,
And lighted at a ruined inn. Tennyson.

It made all their hearts to light. Chaucer.

[The bee] lights on that, and this, and tasteth all. Sir. J. Davies.

On the tree tops a crested peacock lit. Tennyson.

On me, me only, as the source and spring
Of all corruption, all the blame lights due. Milton.

The several degrees of vision, which the assistance of glasses (casually at first lit on) has taught us to conceive. Locke.

They shall light into atheistical company. South.

And here we lit on Aunt Elizabeth,
And Lilia with the rest. Tennyson.