make less distinct the lines that separate the three kingdoms from one another, so that we are led to the conclusion that the mineral kingdom is connected by successive degrees with the vegetable and animal kingdoms, and consequently that matter is one.
Hence the study of mineralogy, giving the word its real signification of a science applying to all unorganized bodies, ought to precede the study of botany and zoölogy, because it is the rational introduction to knowledge respecting the phenomena of Nature. There is manifest in these days an evolution from the sciences called natural toward the physical and chemical sciences, and from the physical and chemical sciences toward the mathematical sciences.
A natural phenomenon is the resultant of multiple actions which make themselves perceived concurrently in its manifestation. It is an equation containing many unknown quantities. There is only one way to resolve it: it is to find a sufficient number of other equations containing the same unknown quantities with different coefficients and exponents, and then to eliminate the unknown elements one after the other. That is the object of experiments, in which man intervenes with his intelligence and his hands to simplify and finally to resolve the problem that he proposes to himself, which is to obtain a complete knowledge of the phenomenon. In every experiment he retains as constants some conditions which he can not wholly get rid of, and limits himself to putting a single variable through its changes. He then makes constant the variable, of which he has just examined the influence, and subjects to modifications one of the other variables which he had previously held as a constant. This work is really the same as to formulate a new equation between different unknown quantities. Every science must therefore rest upon experiment, which alone is capable of leading to the knowledge of the law—that is, to a generalization, and of permitting the student to foresee results. A science which can not generalize or foresee only deserves the name of simple knowledge. Detailed observation translated into minute description is the servant of experimentation, for its task is limited to verification.
The science of inorganic bodies, mineralogy and geology, has been the first to feel the effects of the evolution of the natural sciences toward the exact physical and chemical sciences. Its phenomena present the minimum of complication; it ought, even more than the others, if that is possible, to be founded on experiment, measure, figures, and number.
I have been gratified to find my views on these subjects corroborated by the observations of Professor Mario Pilo, of the Lyceo Balbo in Turin, as recorded in a paper published by him in the "Ri vista di filosofia scientifica," on "The Life of Crystals; or, Outlines for a Future Mineral Biology." This author has collected a large number of results agreeing with the doctrine of the successive and insensible
