to distant generations, to cause a needle to guide the mariner with assurance on the darkest night, to propel a heavy ship against wind and tide without oars or sails, to make carriages ascend mountains without horses at the rate of thirty miles an hour, to convey intelligence with the speed of lightning from continent to continent and under oceans that ancient navigators never dared to cross,—­these and other wonders attest an ingenuity and audacity of intellect which would have overwhelmed with amazement the most adventurous of Greeks and the most potent of Romans.

But the great discoveries and inventions to which we owe this marked superiority are either accidental or the result of generations of experiment, assisted by an immense array of ascertained facts from which safe inductions can be made.  It is not, probably, the superiority of the European races over the Greeks and Romans to which we may ascribe the wonderful advance of modern society, but the particular direction which genius was made to take.  Had the Greeks given the energy of their minds to mechanical forces as they did to artistic creations, they might have made wonderful inventions.  But it was not so ordered by Providence.  At that time the world was not in the stage of development when this particular direction of intellect could have been favored.  The development of the physical sciences, with their infinite multiplicity and complexity, required more centuries of observation, collection and collation of facts, deductions from known phenomena, than the ancients had had to work with; while the more ethereal realms of philosophy, ethics, aesthetics, and religion, though needing keen study of Nature and of man, depended more upon inner spiritual forces, and less upon accumulated detail of external knowledge.  Yet as there were some subjects which the Greeks and Romans seemed to exhaust, some fields of labor and thought in which they never have been and perhaps never will be surpassed, so some future age may direct its energies into channels that are as unknown to us as clocks and steam-engines were to the Greeks.  This is the age of mechanism and of science; and mechanism and science sweep everything before them, and will probably be carried to their utmost capacity and development.  After that the human mind may seek some new department, some new scope for its energies, and an age of new wonders may arise,—­perhaps after the present dominant races shall have become intoxicated with the greatness of their triumphs and have shared the fate of the old monarchies of the East.  But I would not speculate on the destinies of the European nations, whether they are to make indefinite advances until they occupy and rule the whole world, or are destined to be succeeded by nations as yet undeveloped,—­savages, as their fathers were when Rome was in the fulness of material wealth and grandeur.