3. At first sight nothing would appear so profoundly varied, so essentially distinct, as the diverse substances which compose the world. Among the objects in art or nature which daily pass before our eyes, are there two objects which can be accused of a perfect identity? Is it not only a parity of composition? What dissimilarity at the point of view of solidity, of compressibility, of weight and multiple properties of bodies, between atmospheric gas and a thread of gold, between the aqueous molecules in the clouds, and those of the mineral which forms the bony framework of the globe! What diversity between the chemical tissue of the varied plants which decorate the vegetable kingdom, and that of the no less numerous representatives of animal life upon Earth!
However, we can state as an absolute and fundamental truth, that all substances known and unknown, however dissimilar they may appear, either in view of their constitution or in regard to their reciprocal action, are only different forms through which matter presents itself, only varieties into which it is transformed under the direction of the innumerable forces which govern it.
4. Chemistry, of which the progress has been so rapid since the epoch in which I lived, thus far still relegated to the secret domain of magic by its own supporters, — this new science, which one can justly consider the child of this century is, we observe, uniquely based, far more solidly than its elder sisters, upon the experimental method. Chemistry, I say, has had fair play with the four primitive elements which the ancients agreed to recognize in nature. It has shown that the terrestrial element is only a combination of diverse substances varied to infinitude; that the air and water are equally decomposable, that they are the product of a certain number of equivalents of gas; that fire, far from being itself a principal element, is only a state of matter resulting from the universal movement to which it is submitted, and is of a sensible or latent combustion.
In return it has found a considerable number of principles until then unknown, which have appeared to form, by their determined combinations, diverse substances, different bodies, that it (chemistry) has studied by following certain laws, act simultaneously, and in given proportions, in the works operated in the grand laboratory of nature. These principles it has named simple bodies, indicating by that that it considers them primitive and indecomposable, and that by no known operation can they be reduced to parts relatively more simple than themselves.*
* The principal simple bodies are: among non-metallic bodies, oxygen, hydrogen, nitrogen, azoth, chlorine, carbon, phosphorus, sulphur, and iodine; among metallic bodies are gold, silver, platinum, mercury, lead, pewter, zinc, iron, copper, arsenic, sodium, potassium, calcium, aluminum, etc.
5. But there, where the appreciation of man is checked even when he is aided by the most impressionable of his artificial senses, the work of nature continues; there, where the common man accept appearance for reality, is where the practitioner raises the veil, and distinguishes the beginning of things. The eye of him who has detected the mole of nature’s action sees alone under the constitutive materials of the world the primitive cosmic matter, simple and alone, varied in certain countries at the epoch of their birth, divided into solidarities during their life, which at length have become disjointed, and received into the receptacle of life’s boundless whole by decomposition.
6. It is of these questions that we ourselves, spirits, lovers of science, speak when we assert that the opinions we express are merely conjectural. Upon these questions I will either keep silent, or prove my knowledge. To those who then would be tempted to see in my words only a dangerous theory, I will say: learn, if possible, by investigation, the multiplicity of the operations of nature, and you will recognize, that, if one admits not the unity of matter, it is impossible to explain not only the science of the suns and spheres, but without going so far, the germination of a seed in the Earth or the production of an insect.
7. If one observes such a diversity in matter, it is because the forces which have presided at its transformations, the conditions in which they are produced being unlimited in number, the various combinations of matter must be unlimited also.
Then the substance that one desires to comprehend belongs properly to fluids; that is to say, imponderable bodies, or it may be those dressed with the ordinary properties of matter. There is in all the universe only one primitive substance — the cosmic matter, or cosmos of uranography.