as

yellow semi-transparent form, highly inflammable. White phosphorus, formed by exposure under water to light, is less combustible. Black phosphorus is obtained by sudden cooling of melted phosphorus. Red phosphorus can be prepared in various ways, and is combustible only at a high temperature. If we attribute these differences to various grouping of the atoms, and say, "Whatever their form, it is easy, within certain limits, to vary in imagination the adjustment of their homogeneous sides, so to build molecules of several types, and ultimately aggregates of contrasted qualities;" then, in the ultimate stuff of the universe, there are not only myriad types, but myriad types of the same letter. Nor is this all; every one of these letters has its own select list of companions and peculiar terms of fellowship. The hydrogen atom vainly tries in levity, with low figure and light weight, to be intimate with the oxygen element. The reply is, “None of you, or two of you;" and so, throughout, there are certain mathematical proportions. One gas unites with one, two, three, or more volumes of another. There appear even to be special conditions for the likeness "of daisy to daisy, of bee to bee." Then, lest we imagine everything is known, we find that while the same substance is always made up of the same elements, in the same proportion, nevertheless the same elements, in the same proportion, do not always form the same substance: a paradox, yet strictly true. These things forcibly illustrate the omnipresence of mystery. We find, beneath every physical problem, a metaphysical problem, whereof no human cunning can detect the solution.

Now view the printing of the Book.

The ultimate particles of matter cluster into molecules, then into masses, not trying or experimenting to obtain different grouping, or to combine unlike groups, but every one taking its own invariable form. For example, water, wherever and however formed, is always the same substance, and made up of the same component gases in the same relative proportions. "No theory of evolution can be formed to account for the similarity of the molecules throughout the whole region of the stellar universe, for evolution continuously implies continuous

change, and the molecule is incapable of change or decay, of generation or destruction. . . . Though, in the course of ages, catastrophes have occurred and may yet occur in the heavens, though ancient systems may be dissolved and new systems evolved out of their ruins, the molecules out of which these systems are built the foundation stones of the material universe-remain unbroken and unworn." They are endowed with attractive and repellent poles, whose play produces definite forms of crystalline architecture of constant similarity, yet endless diversities, through various and strong interactions.

Every solid body, when slowly deposited from an aeriform or a liquid condition, takes a definite symmetrical shape, which we call crystal-the process we call crystallization. "All crystals, without exception, are solids bounded by plane faces symmetrically disposed about certain straight lines called axes. No mathematician could determine these axes with more accuracy than they are found to exist. Numerical relations of the most remarkable kind exist in the proportions in which alone natural substances will combine, and these numerical relations exist also in plants. Nothing is more striking in botany than the mode in which certain numbers, such as three and five and their multiples, prevail. . . . Can we believe them to be exhibited in nature by a mere concourse of atoms, or by self-existing and self-created proportions of matter without the intervention of Intelligence and Mind?"" Little importance attaches to that unphilosophical theory which assumes that chance, having an eternity wherein to try and fit and combine, did, at length, by a chance arrangement, form the worlds; and, by chance, continued them. Cicero had a word on this "The man who believes this (that the world with all its beauty, with all its fittedness for man, as well as for animal and vegetable life, was made by the chance meeting of atoms) will believe that if a countless number of the letters of the alphabet—their material being either gold or anything else—were thrown in a mass in some place, from these letters ' Professor J. Clerk Maxwell.

2 "On the Limits of Science :" Wm. Forsyth,-Fraser's Mag., Feb. 1875.

shaken out on the ground, there can be formed the annals of Ennius, arranged in such order as to be read continuously."1

In every molecule, formed by combination of separate atoms, we have, as it were, a solar system. The atoms are not supposed to be indefinitely near one another, but of distances great in proportion as are the planets from the sun, and revolve round each other. The distance of a fixed star from us is very great compared with that of the sun, but a portion of matter which, in our most powerful microscope, seems almost indescribably small, may be as wonderfully complex in structure as is the star itself. The molecules build themselves up into definite shapes, but create neither new matter nor new energy; neither the vegetable body nor the animal body, as regards matter and energy, can create anything. All the mystical play of mechanical, chemical, and vital molecular processes leaves the magnitude of matter and the energies unenlarged. Nature, therefore, is not the equivalent of all phenomena; cannot create matter, nor originate energy; it is a something in relation to that which went before; a something in relation to that which will follow. Gravity or energy is not an essential of matter, but that by which it is pressed or pushed about. Hence, matter, in itself, whether ponderous as gold, or dense as steel, "subtile" and ethereal as gas or magnetic fluid, is not self-motive; yet we only know matter by its manifestation of energy, and “we are irresistibly compelled by the relativity of our thought to vaguely conceive some unknown force as the correlative of the known force." 2

The operations of this energy are beautiful and delicate. From a solution of common salt, let the water slowly evaporate, and the minute particles of salt, so minute as to defy all microscopic power, deposit themselves; and, through the clustering of innumerable molecules, a fine crystalline mass of miniature pyramids is raised by structural energy. The ice of our winters is of equally skilled handiwork in definite shapes; precious to the eye of science as the diamond, and purely formed as they are delicately built. The cells of the

1 "De Natura Deorum," ii. 37.

* "First Principles," p. 170: Herbert Spencer.

Mechanism of Worlds.

75

sheath of a straw, when examined by polarised light, are found to have the architecture of a crystal: the molecules are set in definite positions. The exquisite texture of light is a miracle of beauty in its gorgeous colours; a marvel in the invisible rays, which exceed in heat; a wonder of chymic power to the world in the ultra-violet rays; and a mystery, in making all other things to be seen itself unseen. The atmosphere is not only diffused with subtile power, but containing carbonic acid-food for the vegetable world; and oxygen-the support of animal life. All these, whether waves of aether, or atoms coalescing in sky-matter, or matter in invisible masses, move to the music of law.

Pass from the rudiments to the mechanism of worlds.

Diffused matter is contracted into collections of attenuated flocculi, and solidified into masses. If we could mentally see the generation of the movement, the first operation of energy, we might expect, from what we know of things, a slight shiver as of leaves in faintest wind, a throb extending through the sphere of motion, and the whole showing a complication vaster than the mightiest ocean swell. We may conceive of this motion having a rhythm which could be traced in light, heat, electricity, in the spiral arrangements so general among the more diffused nebulæ, and in every particle of matterrhythm prepared for by some primordial condition, and continued by persistence of energy. By contraction, the potential energy would be gradually transmitted into heat and visible motion.

Energy, carrying the moved body in the same straight line for ever, would cause an infinite space, void of everything except the moving body; or if centres of equivalent energy were placed at equal distances, they would remain in equilibrium for ever. How then are the vast curves of the planetary bodies obtained? To represent it mentally, fill an apparent vacuity with an æthereal medium-a species of matter-countless lines radiate from the centre to every side, and along every line this medium presents resistance, so that the exact line on which matter sets out, drawn by attraction to the centre, cannot be continued, but becomes a curve; and a curve the more complex in proportion as the energies are

more numerous and varied. Apply this to nebular condensation, and precipitation of diffused matter into flocculi of denser matter. As the matter moves by gravitational energy, the direction would be, first of all, in a straight line; but the direction being continually influenced by surrounding bodies, themselves in relative movement, rotation and revolution would then be set up, and conditions analogous to those of the sun and solar system be established. The sun, our earth, and the other planets had their own concentrations, say of nebulous ring, gaseous spheroid, liquid spheroid, and spheroid externally solidified. If we regard this energy as merely mechanical, it possesses nothing directive; no more produces a planet than a poem; neither explains the energy of gravity which brings all bodies together, nor that of repulsion which tears them asunder. The pressing and pushing about of matter are not the equivalents of all phenomena; but, as magnetism, heat, and light are held to be different modes of some one universal energy, we regard the attraction and repulsion of matter as manifestations of a mysterious Power, -a Power which, Herbert Spencer says, "transcends intuition and is beyond imagination."

Continue the mechanical investigation:

1. The Earth-The form of the earth is a spheroid or ellipsoid. It is thus accounted for. A detached fluid mass, if at rest in space would assume, by gravitation of its particles, the form of a sphere. When it began to rotate on its axis it would become flattened at the poles, and bulge at the equator. This bulge is now about I in 300, or something like 13 miles of extra matter all round. When separated and aggregated from the nebula which produced the solar system, our earth probably exceeded 40,000 miles in diameter, 60 times more than now, and then the mass took about 291⁄2 days to rotate. The earth's oblateness is proof that it was modelled when in a yielding or plastic condition, before the crust had been formed, when it was an incandescent globe rolling through space, with all the water and other vapourisable matter in a gaseous state. Sir Isaac Newton calculated that "a comet formed of iron would absorb so much heat in its near approach to the sun as to require