Radiance

“ Shafts of light seemed to dart in rapid succession from earth to sky, until at last the vast luminous orb of day rose from the depth of the many-coloured radiance, and with its surpassing glory put everything else to shame. ”

“ To-night not a breath was stirring, the outer radiance was the radiance of stars only, yet so limpid, so lustrous the air that cloudless moonlight could hardly have made every object seem clearer, more distinct. ”

“ In the midst of each flame we saw a radiant being having human form. Presently the lights moved toward one another and made contact, whereupon the two beings in them were seen to be walking side by side. The beings’ bodies were formed of a pure dazzling radiance, white like the radiance of the sun, and much brighter than the yellow light or aura surrounding them. So dazzling was the radiance, like a halo, round their heads that we could not distinguish the countenances of the beings ”

“ That a body of the same structure as the earth should shine with the radiance of the moon merely because sunlight is reflected from it, is in itself a supposition seemingly contradicted by ordinary experience. ”

“ On him the light of star and moon Shall fall with purer radiance down; All constellations of the sky Shed their virtue through his eye. Him Nature giveth for defence His formidable innocence; The mounting sap, the shells, the sea, All spheres, all stones, his helpers be; ”

“ The innumerable images of the solar rays reflected from the innumerable waves of the sea, as they fall upon those waves, are what cause us to see the very broad and continuous radiance on the surface of the sea. ”

“ But he can be visible only by the rays he emits, and which enter the organs of vision. How inconceivably immense, then, must be the quantity of rays which are thrown off in all directions from that luminary which is the source of our day! Every star must likewise be considered as emitting innumerable streams of radiance over a space equally extensive, so that no point in the universe can be conceived where absolute darkness prevails, unless in the interior regions of planetary bodies. ”

“ GRACIOUS MOONLIGHT Even as the moon grows queenlier in mid-space
When the sky darkens, and her cloud-rapt car
Thrills with intenser radiance from afar,—
So lambent, lady, beams thy sovereign grace
When the drear soul desires thee. ”

“ Your mind struggles pleasantly between the dancing radiance round the hearth of a young man and his recent bride and the twittering flight of birds in spring about their new-made nest. You feel the merry bounding of a ship before the breeze, and watch the tuneful feet of rosy girls as they twine their last and merriest dance in a splendid ball-room, and find yourself in the brilliant circle of a crowded theatre as the curtain falls over a light and airy scene. ”

“ For there is no doubt, that the light of the heavenly bodies not only far surpasses the vivid appearance of white, but even the light of any flame (with which we are acquainted) in the vigor of its radiation. The immense velocity of the bodies themselves, which is perceived in their diurnal motion, and has so astonished thinking men, that they have been more ready to believe in the motion of the earth, renders the motion of radiation from them (marvellous as it is in its rapidity) more worthy of belief. ”

“ That which before lay buried in the shade of night is itself now a radiator of the luminous fluid. Mark the genial warmth that comes as the sister of light; then stand by the side of the experimentalist and watch the point on which he directs the shining focus, and in an instant see iron melt and stones run like water, under the fervent heat! Now look upward to the heavens, where the falling drops of rain have formed a natural prism in the rainbow, and shown that the beam of pure whiteness, refracted into various rays, glows with all the tints that adorn the garden of nature. ”

“ In one word, the sphere of darkness in which I floated seemed to be filled with points of light, while the absolute blackness that surrounded them, the absence of the slightest radiation, or illumination of space at large, was strange beyond expression to an eye accustomed to that diffusion of light which is produced by the atmosphere. ”

“ From the very brightness of the light of some of the fixed stars we may infer the intensity of that dark radiation, which is the precursor and inseparable associate of their luminous rays.
We thus find the luminous radiation appearing when the radiant body has attained a certain temperature; or, in other words, when the vibrating atoms of the body have attained a certain width of swing. In solid and molten bodies a certain amplitude cannot be surpassed without the introduction of periods of vibration, which provoke the sense of vision. ”

“ But something seems to approach us. What are those pale rays of light which we can faintly see a long, long way before us—rays pale and soft, quite unlike those flaming fires we have left behind us? Surely these do not denote the presence of human activity! As we continue to advance, these pale flakes of light—resembling nothing so much in appearance as molten lead—which at first were scanty and isolated, gradually expand, and leave only narrow strips of darkness to divide them into fantastic shapes. ”

“ There is absolutely no philosophical basis for distinction between the visible and invisible radiations of the sun, except in the one point of vibration-frequency—their pitch, to use the analogy of sound. The expressions thermal, luminous, and chemical rays are apt to be misleading. All the waves of solar radiation are carriers of energy, and when intercepted do work, producing heat, or vision, or chemical action, according to circumstances. ”

“ It is defined as a substance hot to the feel. [Heat, then, and light are identified as one substance.] [3]
"It has the qualities of earth except smell, taste, and gravity. It is eternal, as atoms; not so, as aggregates.
"Organic luminous bodies are beings abiding in the solar realm. The visual ray, which is the organ of sight, is lucid. Unorganic light is reckoned fourfold: earthy, celestial, alvine and mineral. Another distinction concerns sight and feel; as light or heat may be either latent or manifest, in respect of both sight and feel, or differently in regard to either. ”

“ These nerve vibrations are sent over the optic nerve to the brain, where they take on the shape, size and colors of the Sun.
Reflection of Light.—The flame of a match, or a candle, an oil or a gas lamp, or Sun, comet or meteor, produces its own light, and for this reason these bodies are called self-luminous—that is, they are themselves the source of light.
All other objects which do not produce light, such as an apple, a stone, the Earth and other planets and moons are called non-luminous bodies. ”

“ Dismissing for the present the theory of undulations, it will be necessary to examine the phenomena of light, regarding it as radiant matter, without reference to either of the contending theories.
[Pg 265]
Light issues from the sun, passes through millions of miles to the earth, and as it falls upon different substances, a variety of effects are apparent. There is a certain class of bodies which obstruct the passage of the rays of light, and where light is not, a shadow is cast, and the substance producing the shadow is said to be opaque. ”

“ The whole body of vibrations caused by the sun is termed radiation, or, more commonly, rays; and consists of sets of waves which vary considerably in their dimensions and rate of recurrence, but of which the middle portion only is capable of exciting in us sensations of light and colour. Beginning with the largest waves, which recur at the longest intervals, we have first those which produce heat-sensations only; as they get smaller and recur quicker, we perceive a dull red colour ”

“ Beyond our atmosphere the sun would appear a rayless orb of fire in the midst of a black concave. The equal diffusion of its light on earth is owing to the refraction of the rays by the atmosphere, and their reflection from other bodies. Light consists either of vibrations propagated through a subtle medium, or of numerous minute particles repelled in all directions from the luminous body. ”

“ All that has been said with respect to the radiations which affect our eyes, and which we call light, applies also to those radiations which do not produce a luminous impression on our eyes, for the phenomena of interference have been observed, and the wave-lengths measured, in the case of radiations, which can be detected only by their heating or by their chemical effects. ”

“ It is enough for humanity to have arrived at this for the present—for we have not yet sounded the heights or depths of even the first Seven radiations which we all agree to recognise. We admit seven tones of music, and seven tones of colour, but what of our seven rays of light? We have the ‘violet ray,’ the ‘X ray’—and a newly discovered ray showing the working bodily organism of man,—but there are Seven Rays piercing the density of ether, which are intended for the use and benefit of the human being, and which are closely connected with his personality, his needs and his life. ”

“ What they have acquired more in the day they lose at night by radiation, the force of which depends on the state of the surface of the radiating body, the interior arrangement of its particles, and, above all, on the clearness of the sky, that is, on the transparency of the atmosphere and the absence of clouds. ”

“ Radiating in every direction, from millions of centric points, run shivers of undulation manifested in endless metamorphosis as heat, or light, or actinism, as magnetism or electricity. Crossing one another in every imaginable way, as if all space were crowded with a mesh-work of nerve-threads, these motions go on forever in a harmony that nothing disturbs. ”

“ It is hardly necessary to occupy time with experiments in showing that a ray of light can be reflected and refracted by mirrors and prisms, and converged or diverged by transparent lenses. These are simple optical facts, and if you are not familiar with them it will be easy for you to make their acquaintance by studying any simple book upon optics; but I should like to draw your attention to the fact that, in addition to rays of light and electric radiation, we are acquainted with another kind of radiation, which is also susceptible of being refracted, and that is commonly called dark heat. ”

“ Two bright lights may be made to produce darkness.—If two pencils of light radiate from two spots very close to each other in such a manner that they cross each other at a given point, any object placed at that line of interference will be illuminated with the sum of the two luminous pencils. If we suppose those rays to move in waves, and the elevation of the wave to represent the maximum of luminous effect, then the two waves meeting, when they are both at the height of their undulation, will necessarily produce a spot of greater intensity. ”

“ To add yet to the wonder, we may suppose that these rays may be subtle as magnetic beams, which penetrate brass and stone as easily as light doth glass; and at the same time they may be as swift as light, which reaches the most amazing distance of several millions of miles in a minute. By this means, since the light of the sun pervades all secret chambers in our hemisphere at once, and fills all places with direct and reflected beams, if consciousness belonged to all those beams, what a sort of omniscient being would the sun be! ”

“ Instead of the beautiful azure of the sky, and the colours which distinguish the face of nature by day, we should see nothing but an abyss of darkness, and the stars shining from a vault as dark as chaos. Thus there would be no day, such 61 as we now enjoy, without the atmosphere: since it is by the refraction and reflections connected with this aerial fluid that light is so modified and directed, as to produce all that beauty, splendour and harmony, which appear on the concave of the sky, and on the objects which diversify our terrestrial abode. ”

“ Radiation. The passage of light or heat in rays, or straight lines; these being projected from every luminous, or heated point, in all directions.
Radius. The distance from the centre of a circle, to its circumference; or one half of its diameter. In the plural denominated radii.
Rainbow. An appearance in the atmosphere, occasioned by the decomposition of solar light, in its refraction, and reflection, in passing through drops of rain. The bow can be seen, only when the sun is near the horizon, when the back is turned towards it, and there is a shower in the opposite direction. ”

“ At noon day we should see the sun like an intensely brilliant globe shining in a sky as black as ebony, like a clear fire in the night seen in the midst of an extensive field, and his rays would show us the adjacent objects immediately around us; but the rays which fall on the objects remote from us would be for ever lost in the expanse of the heavens. ”

“ For as we dropped swiftly down toward that world we saw at last that the faint light which illuminated it was not artificial light, or reflected light, but light inherent in itself, since all the surface of the mighty sphere glowed with the same phosphorescent light, its plains and hills and valleys alike feebly luminous, with the soft, dim luminosity of radio-active minerals. ”

“ Of heat; reflexion; refraction.The conclusions arrived at in optics necessarily entered as fundamental ideas in thermotics, or the science of heat; for radiant heat moves also in straight lines, undergoes reflexion, refraction, double refraction, polarization, and hence the theory of transverse vibrations applies to it. Heat is invisible light, as light is visible heat. Correct notions of radiation originated with the Florentine academicians, who used concave mirrors; and, in the cold-ray experiment, masses of ice of five hundred pounds weight. ”

“ What mainly holds the light in our atmosphere after the sun has retired behind the earth is, I imagine, the suspended matter which produces the blue of the sky and the morning and the evening red. Through the reverberation of the rays from particle to particle, there must be at the very noon of night a certain amount of illumination. ”