critical examination of the facts will show that it does neither." And the chapter then goes on to show that the change is from an indefinite incoherent homogeneity to a definite coherent heterogeneity. Further qualifications contained in a succeeding chapter bring the formula to this final form: "Evolution is an integration of matter and concomitant dissipation of motion; during which the matter passes from an indefinite, incoherent homogeneity to a definite, coherent heterogeneity; and during which the retained motion undergoes a parallel transformation."
Now, if these various traits of the process of evolution are kept simultaneously in view, it will be seen that most of Mr. Cliffe Leslie's objections fail to apply. He says: "The movement of language, law, and political and civil union, is for the most part in an opposite direction. In a savage country like Africa, speech is in a perpetual flux, and new dialects spring up with every swarm from the parent hive. In the civilized world the unification of language is rapidly proceeding." Here two different ideas are involved—the evolution of a language considered singly, and the evolution of languages considered as an aggregate. Nothing which he says implies that any one language becomes, during its evolution, less heterogeneous. The disappearance of dialects is not a progress toward the homogeneity of a language, but is the final triumph of one variety of a language over the other varieties, and the extinction of them: the conquering variety meanwhile becoming within itself more heterogeneous. This, too, is the process which Mr. Leslie refers to as likely to end in an extinction of the Celtic languages. Advance toward homogeneity would be shown if the various languages in Europe, having been previously unlike, were, while still existing, to become gradually more like. But the supplanting of one by another, or of some by others, no more implies any tendency of languages to become alike than does the supplanting of species, genera, orders, and classes of animals, one by another, during the evolution of life, imply the tendency of organisms to assimilate in their natures. Even if the most heterogeneous creature, man, should overrun the earth and extirpate the greater part of its other inhabitants, it would not imply any tendency toward homogeneity in the proper sense. It would remain true that organisms tend perpetually toward heterogeneity, individually and as an assemblage. Of course, if all kinds but one were destroyed, they could no longer display this tendency. Display of it would be limited to the remaining kind, which would continue, as now, to show it in the formation of local varieties, becoming gradually more divergent; and the like is true of languages.
In the next case Mr. Leslie identifies progressing unification with advance toward homogeneity. His words are: "Already Europe has nearly consolidated itself into a heptarchy, the number of states into which England itself was once divided; and the result of the American