Page images
PDF
EPUB

Earth-clouds excluded the Light.

153

Higher knowledge discerns that mind and body, spirit and matter, have reciprocities of power; and their scope gives fitness to the whole man.

If the sun was so far conditioned as to shine out beyond his own vapours, the hypothesis is that earth-clouds excluded the light from our planet, and covered the surface with gloomy obscurity, like that of evening and early morn. Our earth, with this robe of vapour, and earlier separated from the original mass than were Venus and Mercury, would probably, to a distant beholder, have fleecy shifting, dissolving bands, dense masses of clouds driven of winds and tossed, such as we now behold by telescopic examination of the planet Jupiter. This vast planet is encircled by great cloud-belts, such as the sun is incompetent to raise. Cloud-layer upon cloud-layer covers the seething surface which appears to be passing through those stages which marked the earth's early course; and, small as is the visible sun there, the skies seem in formation by establishment of a firmament like our own. Analogy holding everywhere, is God's name written in everything.

This may be expressed in another form. The firmament is not strictly the air itself, still less a solid vault, falsely conceived to exist, but that visible hemisphere of sky which incloses the earth and sea. The optical view, in explaining the sacred narrative, should be explained and enlarged by an instructed intellect. Intellect tells us—"Were the matter of the universe cast in cold detached fragments into space, and there abandoned to the mutual gravitation of its own parts, the collision of the fragments would in the end produce the fires of the stars." 1 This separating of materials, then the gathering of meteoric masses into centres of conflagration, give us one star differing from another star, and the firmamental expanse. Further, we are told that "the planets exterior to Mars, Jupiter, Saturn, specially the best known of them, appear to be spheres of water and of aqueous vapour, combined, it may be, with atmospheric air.

It was agreeable to the general scheme that the excess of water and vapour should be packed into rotating masses, such as are Jupiter and Saturn, Uranus and Neptune. Thus the vapour which otherwise would have wandered loose about the atmosphere, was neatly wound into balls, which "The Constitution of Nature: " Prof. Tyndall.

again were kept in their due place by being made to revolve in nearly circular orbits about the sun." 1 The scientific theory is, and it can be no more than theory, that for our earth, with a robe of vapour around, seems to have been formed a sensible expanse, or middle region of clearer atmosphere, separating the waters depositing below from those drawn upward; and transferring, yet containing the sea of mist, by passing it into pure invisible vapour. Scripture states-the Lord bound up the waters in the thick cloud (Job xxvi. 8), in His discretion stretched out the heavens (Jer. x. 12), caused the vapours to ascend from the ends of the earth, made lightnings for the rain, and brought the wind out of His treasures (Ps. cxxxv. 7). Could we understand it all, we should raise the sable curtain that hides the work of Providence.

"2

"Divide the waters from the waters." "The clouds are, in Scripture metaphor, the bottles of heaven. These are the instruments by which, when the windows of heaven are opened, some of the waters above the firmament are transferred from their celestial reservoir, and descend in showers to rejoin, by the springs and rivers, the gathering of the waters in seas below the firmament.' Mists and clouds are said to be formed of a multitude of hollow vesicles with exceedingly thin covering. These vesicles vary from 1'4222 to 12620 of an inch in diameter. This theory—that water in the clouds is in the state of small vesicles, or bladders, containing air-is not now received. The particles of water are so small and so light in weight that they float in the atmosphere, the air being as an elastic cushion beneath them. The aerial body of the atmosphere is of distinct and separate character from the vaporous portion contained within its interstices. By the formation of clouds, their elevation into the air, their easy and rapid movement by means of the atmosphere, the earth is refreshed with dew and moistened with water; while, by pressure of the very atmosphere into which moisture is raised, too quick evaporation of liquids and dispersion of many solids are prevented. It was thought that we knew nearly all as to the constituents of our atmosphere; but Lord Rayleigh, discovering argon as another element of it, we find this argon has a remarkable 1 "Theory of the Solar System :" Dr. Whewell.

2 "The Bible and Modern Thought;" Notes, Rev. T. R. Birks.

[blocks in formation]

property. The atoms move backwards and forwards, not rotate, spin round their own centre, as most atoms do. The atmosphere has been ever the same during historic time, for the air contained in a jar, buried at the destruction of Pompeii, was like that now covering the earth; the breezes of Africa, wind on the lofty Alps, the atmosphere of England, are of uniform constitution. Bearing the breath of life to animals, and nourishment to plants, it is a faithful conservatory of blessings

"The earth waxed proud withal
For sweet dews that on it fall."

Chaucer.

If, in popular conception of the firmament, we take it as the sensible limit between the visible and invisible; then all water visible to the senses, whether in seas or in clouds, is described as under the firmament; and all that which is invisible or concealed from the senses is stated to be above the firmament. Out of this state of invisibility the rain appears to fertilise the earth. This is opening the windows of heaven, pouring out of the bottles, the descent of the waters from above the firmament to mingle with those below. If we stand and look into the azure sky when the clouds give out their evaporation, or consider the rain descending through bands of light, we discern a fulness in the words "God made the firmament, and divided the waters," to which modern art cannot add, and he is unwise who counts his guesses truths.

The operations which formed the firmament, gathered the waters, upheaved the dry land, prove that the sun was already in existence, exerting those mighty energies by which, in conjunction with earth-powers, land, sea, air, became beautiful abodes of life.

We may now ascend from these arrangements, by means of which sunlight pierced to the earth and became beneficial, to the phenomena of light as affecting our firmament. Wisdom delights to discover the affinity of opposites.

Tracing light, high as its source, we arrive at particles of matter vibrating as the particles of a tuning-fork vibrate to produce sound. The waves differ in size, form, energy. All larger than the red, all smaller than the violet, are incompetent to excite vision. Of those exciting vision, the largest may

be of thousands-fold more energy than those of the smallest ; and of all the waves, visual and non-visual, millionsfold. They meet different degrees of hindrance on passing into refracting substances, indeed are actually pulled asunder when sent through a refracting prism, and pure unsifted white light separates into an infinity of colours; but our sight is limited to seven, called prismatic-red, orange, yellow, green, blue, indigo, violet.

The waves, impinging on ordinary clouds, are divided into a reflected part and a transmitted part; when they pass from light air into dense, or from dense air into light, a portion of the wave-motion is always reflected, and the reflected light enlightens our firmament. This light is blue, because blue is reflected; orange and red are transmitted, or break through, being more forcible; the others are scattered, and blue is the chief colour of scattered light. Transmitted light, that which comes to us, appears yellowish when short distances are traversed; but, as the sun descends toward the horizon, the atmospheric distance increases, and violet, indigo, blue, and a portion of green, are abstracted in succession; and the firmament colours from yellow to orange, and through orange to red. Thus we have, at noon, deep azure; at sunset, the warm crimson glow hung as a curtain between our earth and the black height of infinite space; at midnight—" The gorgeous arch, with golden worlds inlaid."

We can generate artificial skies by means of vapours. These vapours are aggregates of molecules of matter, and every molecule is an aggregate of atoms; a molecule of aqueous vapour being two atoms of hydrogen and one of oxygen; a molecule of sulphurous acid being one atom of sulphur and two of oxygen; a molecule of ammonia being three atoms of hydrogen and one of nitrogen. They have motions of their own as wholes, the atoms have motions of their own as parts, and the atoms approach one another or recede, as the separating forces are overcome, cease to act, or acquire force. They cannot altogether part company because, besides the repulsive, there is an attractive force; and the position of equilibrium is that point at which attraction and repulsion are equal to one another. Take a glass tube filled with sulphurous acid gas, place it in a dark room, send through it a powerful beam of light; the vessel

Action of the Firmament.

157

seems empty, but soon a beautiful sky-blue colour is seen along the track of the beam. Various other colourless substances, of the most different properties, optical and chemical, may be experimented upon to produce the blue of the sky, luminous clouds, and splendid iridescences. New and true ideas enlarge and enrich our knowledge.

1

These colours are called forth in the sky by the shining of light upon matter; and minute spheres of water, and minute crystals of ice, give grain to the blue vault. Space, traversed by rays from all suns and stars, is itself unseen; and the ether which fills that space, and by its motions lights up the universe, is invisible. "Colour depends solely upon the rate of the oscillations of the particles of the luminous body, red light being produced by one rate, blue light by a much. quicker rate, the colours between red and blue by the intermediate rates." Take a tube containing air and amyl vapour. They are both invisible. Converge the rays of an electric lamp to a focus in the middle of the tube. For an instant it is dark, but quickly the beam darts through a luminous white cloud, the molecules of the nitrite of amyl are shaken asunder, there is a shower of liquid particles, and the flash is like "a solid luminous spear." This separation, or breaking up, is effected by exciting differential motions among the atoms, and the motions are introduced by the shock of light-waves from the lamp. The waves most effectual in shaking asunder compound molecules are not the red and the ultra-red, but those of least mechanical power, the violet and the ultra-violet. They are probably millions of times less than the ultra-red waves, yet the great are powerless and the less are potent. Sky-matter, or matter in the skyey conditions, which we are now acquainted with, the basis of light, consists of particles so infinitesimal that the bewildering vastness of distances in stellar space has here to be reversed; by no possible exertion of our present faculties can we picture the ultimate atom. Sir John Herschel calculated that the matter composing the tail of a comet 100,000,000 miles in length and 50,000 miles in diameter, would do little more than fill a wheelbarrow; and, as to all the matter in our firmament, Professor Tyndall says "I have sometimes thought that a lady's portmanteau

1 "Chemical Rays and the Structure and Light of the Sky:" Prof. Tyndall.

« PreviousContinue »