Word Finder - illumination

definition

The act of illuminating, or supplying with light; the state of being illuminated.

definition

Festive decoration of houses or buildings with lights.

definition

Adornment of books and manuscripts with colored illustrations. See illuminate (transitive verb).

definition

Splendour; brightness.

definition

Enlightening influence; inspiration.

There is everywhere a certain illumination due to it.

We will now investigate the total illumination distributed over the area of the circle of radius r.

The electric lamp a gives illumination of the webs in a dark field, nearly in the manner described for the Cape transit circle micrometer; the intensity of illumination is regulated by a carbon-resistance controlled by the screw b.

They give very steady illumination on fluorescent screens.

The dorsiventrality of the prothallus has been shown to depend mainly on the illumination, the filamentous form being retained in feeble light; a similar result is obtained when the prothalli are cultivated in water.

Their absolute freedom from diffraction, the perfect control of the illumination and thickness of the lines, and the accuracy with which it will be possible to construct scales for zone observations will be important features of the new method.

Owing to the variable illumination of the selenium thus produced, the resistance of the latter, and therefore the intensity of the current sent through the line to the receiving station by the battery, will be altered accordingly.

The illumination is intermittent, and appears to be under the control of the insect's nervous system.

For the dark rings Ji(z) =o; so that the fraction of illumination outside any dark ring is simply Jo 2 (z).

In estimating theoretically the resolving power on a double star we have to consider the illumination of the field due to the superposition of the two independent images.

This is the main transpiring tissue, and is protected from direct illumination and consequent too great evaporation.

The most constantly occurring changes that beset a plant are connected with illumination, temperature, moisture, and contact with foreign bodies.

The stem, by pointing directly to the light source, secures the best illumination possible for all of its leaves, the latter being distributed symmetrically around it.

For the illumination of large stations by night electric arc lamps are frequently employed, but some authorities favour high-pressure incandescent gas-lighting.

Ancient philosophers, who had not the Scriptures, received direct illumination from God, and only thus can the brilliant results attained by them be accounted for.

In like manner we may find the illumination in any other direction, and it is obvious that it vanishes when sin 0 is any multiple of A/a.

If r, or z, be infinite, Jo(z), J 1 (z) vanish, and the whole illumination is expressed by 71-R 2, in accordance with the general principle.

In any case the proportion of the whole illumination to be found outside the circle of radius r is given by J02(z)+J12(z).

But this procedure (apart from the question of illumination) is open to the objection that it makes excessive demands upon accuracy.

We have ultimately G =o, H = (7rV)- 1, so that 1 2 = I / 12V 2, or the illumination is inversely as the square of the distance from the shadow of the edge.

We will next suppose that the light is transmitted by a slit, and inquire what is the effect of varying the width of the slit upon the illumination at the projection of its centre.

After this so rapid was the progress of this new mode of illumination that in the course of a few years it was adopted by all the of gas principal towns in the United Kingdom for lighting streets as well as shops and public edifices.

Assent in religion as in everything else he could justify only on the ground of its harmony with reason; professed " illumination without search, and certainty without proof " was to him a sign of absence of the divine spirit in the professor.

A slight shift in the angle of illumination reveals that this critter has some wonderfully metallic green coloration.

Radiometric corrections may be necessary due to variations in scene illumination and viewing geometry, atmospheric conditions, and sensor noise and response.

The imperial crown symbolizes the transcendent illumination or light of the 8th degree, the one that embraces and governs everything else.

In low light, the inbuilt photo light provides illumination to capture video or still images.

The yellowing and subsequent casting of leaves, for instance, is a very general symptom of disease in plants, and may be induced by drought, extremes of temperature, insufficient or excessive illumination, excess of water at the roots, the action of parasitic Fungi, insects, worms, &c., or of poisonous gases, and so forth; and extreme caution is necessary in.

All chlorophyll plants require light, but in very different degrees, as exemplified even in the United Kingdom by the shade-bearing beech and yew contrasted with the light-demanding larch and birch; and as with temperature so with light, every plant and even every organ has its optimum of illumination.

It may be due to insufficient illumination (Etiolation), as seen in geraniums kept in too shaded a situation, and is then accompanied by soft tissues, elongation of internodes, leaves usually reduced in size, &c. The laying of wheat is a particular case.

Neoplatonism owes its form to Plato, but its underlying motive is the widespread feeling of self-despair and the longing for divine illumination characteristic of the age in which it appears.

Herodotus describes the oil pits near Ardericca (near Babylon), and the pitch spring of Zacynthus (Zante), whilst Strabo, Dioscorides and Pliny mention the use of the oil of Agrigentum, in Sicily, for illumination, and Plutarch refers to the petroleum found near Ecbatana (Kerkuk).

The planets in question appeared in the telescope as star-like objects which could be compared with the stars with much greater accuracy than a planetary disk like that of Mars, the apparent form of which was changed by its varying phase, due to the different directions of the sun's illumination.

When light passes through a small circular or annular aperture, the illumination at any point along the axis depends upon the precise relation between the aperture and the distance from it at which the point is taken.

Such a plate has the power of a condensing lens, and gives an illumination out of all proportion to what could be obtained without it.

From the general formula (2), if A be the area of aperture, 102 = A2 / x2 f (7) The formation of a sharp image of the radiant point requires that the illumination become insignificant when, n attain small values, and this insignificance can only arise as a consequence of discrepancies of phase among the secondary waves from various parts of the aperture.

In the direction (suppose horizontal) for which n=o, /f=sin 0, the phases of the secondary waves range over a complete period when sin 0 =X/a, and, since all parts of the horizontal aperture are equally effective, there is in this direction a complete compensation and consequent absence of illumination.

When sin 0 = 2A/a, the phases range one and a half periods, and there is revival of illumination.

The illumination at B due to P then becomes comparatively small, indeed for some forms of aperture evanescent.

On either side of any one of them the illumination is distributed according to the same law as for the central image (m = o), vanishing, for example, when the retardation amounts to (mn t 1)X.

Expressions suitable for discussion when v is large were obtained 1 In experiment a line of light is sometimes substituted for a point in order to increase the illumination.

If the eye, provided if necessary with a perforated plate in order to reduce the aperture, be situated inside the shadow at a place where the illumination is still sensible, and be focused upon the diffracting edge, the light which it receives will appear to come from the neighbourhood of the edge, and will present the effect of a silver lining.

But the illumination of the bow is so weakened by the repeated reflections, and the light of the sun is generally so bright, that these bows are rarely, if ever, observed except in artificial rainbows.

This was first suggested by Thomas Young, who showed that the rays producing the bows consisted of two systems, which, although emerging in parallel directions, traversed different paths in the drop. Destructive interference between these superposed rays will therefore occur, and, instead of a continuous maximum illumination in the direction of minimum deviation, we should expect to find alternations of brightness and darkness.

From the prominence of the lights the festival is also known as the "Festival of Lights" or "Illumination" (Talmud).

The 10th century, by means of this illumination of one of the darkest regions of disease, may diminish human suffering enormously, and may make habitable rich and beautiful regions of the earth's surface now, so far as man's work is concerned, condemned to sterility.

The discoveries of the separate paths of sensory and motor impulses in the spinal cord, and consequently of the laws of reflex action, by Charles Bell and Marshall Hall respectively, in their illumination of the phenomena of nervous function, may be compared with the discovery in the region of the vascular system of the circulation of the blood; for therein a key to large classes of normal and aberrant functions and a fertile principle of interpretation were obtained.

Before his illumination he had been instructed by dreams, and enjoyed extraordinary visions, and heard mysterious conversations.

All the space behind the mirror will become dark, and all the space in front of the mirror will acquire an exalted illumination.

Whatever this increased illumination may be, it can be precisely imitated by removing the mirror and placing a second lighted candle at the place occupied by the optical image of the first candle in the mirror, that is, as far behind the plane as the first candle was in front.