motions in this case. The harmonies of musical sounds are in thirds, fifths and octaves. Nothing in light is similar to that. All the facts of photography are unlike anything in sound. One is evanescent, the other permanent. Light fixes itself so as always to return the same image, and in all things, especially in the organic world, its paintings are as substantial as the living structures on which they are made.

Considering, then, light as a force, each color must be a clear and distinct division of that force, produced by causes that are independent of each other. When they operate together they produce a certain harmonious effect. But they are capable of separation, and when separated no one will do the work of another, or produce the effect of another. The portion of ether whose motions give the sensation of red will never adopt the wave-motion of any other color. Its vibratory tension is its own, as distinct from the others as the strings of a harp are from each other. As before remarked, the white light is more brilliant than that of its component colors. The vividness of the red diminishes down through the other colors of the spectrum until the violet is reached, when the waves are so narrow and rapid that scarcely any light is perceptible. It is the faintest and softest of all the colors of the spectrum. The wave-motions are too short and quick to dazzle, or strongly excite, the visual organs. These distinct wave-motions strongly suggest that they result from different kinds of the elastic medium, each kind having its distinct tension and measure of movement.

But there are portions of the spectrum that are not visible;on one side, because the waves are too long and slow, and on the other because they are too short and quick to excite the sense of vision. But we find that both of them were components of the pencil of light, which the prism decomposed. The ultra red in the spectrum is where the thermal portion is deposited and the ultra violet receives the chemical portion. The pencil of light in passing through the triangular prism is refracted, and the different colors, including heat and actin

ism, or chemical energy, are differently refracted, as is shown in the subjoined figure:

Chemical

Violet

Indigo

Blue

Green

Yellow

Orange

Red

Heat

No human skill has been able to change this relation of the component parts of the spectrum to each other, or to make one correlate into another. The heat in the ultra red may be condensed by a lens so as instantly to ignite blackened paper, or make platinum foil red-hot, and the chemical force on the other side of the spectrum may in like manner be made to exhibit chemical reactions. But they always occupy their respective places in the spectrum, showing that they are several and distinct forces, each having its peculiar refrangibility and wave-motion.

But there are other modes of decomposing a ray of light, if we will so understand the teachings of experiments. I quote the following from a distinguished English scientist who construed the result very differently from myself. Mr. Grove, laboring to prove his favorite theory of the correlation of forces, unconsciously to himself, gives us another mode of analyzing a beam of light. He says:

"In my lecture in 1843 I showed an experiment, by which the production of all other forces by light, is exhibited. I may briefly describe it. A prepared daguerreotype plate is enclosed in a box filled with water, having a glass front, with a shutter over it. Between this and the plate is a gridiron of silver wire, the plate is connected.

with one extremity of a galvanometer coil, and the gridiron of wire with one extremity of Brequet's helix, an elegant instrument formed by a coil of two metals, the unequal expansion of which indicates slight changes of temperature. The other extremities of the galvanometer and helix are connected by a wire, and the needles brought to zero. As soon as a beam of either daylight or oxyhydrogen light is, by raising the shutter, permitted to impinge upon the plate, the needles are deflected. Thus, light being the initiating force, we get chemical action on the plate, electricity circulating through the wires, magnetism in the coil, heat in the helix, and motion in the needles."

An experiment is a question put to Nature. But if the answer is misinterpreted, or not understood, its value is lost. In this experiment, the result revealed two other elements in the complex beam of light, electricity and magnetism, with two manifest in the spectrum, heat and chemical force, found in the invisible part of the spectrum.

Cohesion, which unites atom to atom, and molecule to molecule, to make up solids, is another element. It has analogies with actinism, but analogies are not identities, and parallels between different elements of matter, or of ether, do not extend far. The All-Wise Creator is too rich in resources to repeat any of his processes or productions. Cohesion is also analogous to, but not identical with, Gravitation, which imparts weight to all material substances, holds the countless orbs in their places, directs and controls their motions in their spheres, and preserves the harmony of the Universe. As Newton enunciated it, "Gravitation is a force which binds every atom in the universe to every other atom." And though he discarded the undulatory theory of light, in his letter to Bentley he distinctly avows the belief that the atoms and orbs were held together by some intermediate force, or thing, extending from one to the other. Cohesion. and Gravitation are similar in one respect, that is, their force diminishes with the increase of their squares of distance. But their difference is, that cohesion ceases to operate at

any sensible distance, while gravitation operates at any imaginable distance.

We thus find by the evidence of our senses twenty distinct ethereal elements, or forces, which are all the forces recognized by many physicists. It is not necessary to our argument that twenty elements of ether be enumerated; seven, thirteen or twenty will serve our purpose. It is sufficient for us to show that ether is complex, having several welldefined elements, with distinct functions, actions and effects. We have seen that Grove found electricity, magnetism, heat and actinism in a pencil of light, and yet how unlike these forces or elements are in all their physical qualities. Besides their sensible qualities as forces, light moves through space at the computed rate of 194,000 miles per second, but electricity has a velocity of 288,000 miles per second.

AFFECTION OF ETHEREAL FOR MATERIAL ELEMENTS.

Electricity associates with silks, furs, amber, glass, gums and water; but differe tly. One manifestation of it is called resinous, the other vitreous, positive and negative. It is found to be a constituent element, as a means of offense or defense of certain fishes, which have special organs for its generation. Oxygen and fluorine are the most active of the material elements, the builders and destroyers of so many structures of nature, which may be referred to their being clothed with armatures of chemical elements of great energy. The thermal element is more intimate with some bodies than others. Water takes heat reluctantly; some of the metals rapidly. It requires thirty times more heat to raise water to the temperature of 212° Fah. than mercury. This subject will be noticed again.

Franklin suggested that every atom or molecule of matter was enveloped in a spherule of electricity, with its axis and poles. Later physicists contend that each atom and molecule had an atmosphere of electricity and chemical energy com

bined, with separate axes and poles. Mossotti went further, and held that each had an envelope of general ether around it, and refers atomic and molecular forces, cohesion and gravitation, to its influence. I am inclined to think there is some truth in all these hypotheses, but not the whole truth. The adhesion of some ethereal elements to one or more material elements, in preference to others, the indifference of two or more material elements to each other until united by the influence of an ethereal element, as instanced by hydrogen and oxygen, which are indifferent to each other, but unite by electricity with great energy, and water results, or oxygen and chlorine combined by the same force, and hydrochloric acid is formed;-the allotropic state of several elements, as carbon, oxygen, etc., lead me to conclude that ethereal as well as material elements have their affinities, and the results with matter depend upon the material coatings of ether. Instances of this kind might be adduced almost indefinitely. The whole vegetal kingdom, whose material constituents are so similar and whose qualities are so varied, must result from some combination of ethereal with material elements.

Gasification of solids and the evaporation of fluids can only be satisfactorily explained on the hypothesis of ethereal envelopes of the atoms and molecules. By heat the most refractory substances can be converted into gas, so that even gravitation loses its influence upon the atoms while they are separated from each other, and float in the air like thistledowns. Water is 815 times heavier than air, and yet at how low temperatures will evaporation take place, and how high will vapor ascend to where the atmosphere is vastly less dense than at the ground. Cirrus clouds frequently are seen at an elevation of 30,000 feet (five miles) above the earth; what other body can we conceive sufficient to lift those atoms and molecules to such heights than the ethereal balloons to which they have been committed? Again, the freezing of water, which expands in the act of congelation, is explainable on this hypothesis.