systems, a sense of repose in illimitable vastness and immutable
necessity.

But the Vasco de Gama of his day was Leibnitz. His triumphant
optimism rounded the Cape of theological Good Hope. He gave the
chief impulse to modern intellectual commerce. Full freighted, as he
was, with Western thought, he revived the forgotten interest in the
Old and Eastern World, and brought the ends of the earth together.
Circumnavigator of the realms of mind, wherever he touched, he
appeared as discoverer, as conqueror, as lawgiver. In mathematics,
he discovered or invented the Differential Calculus,--the logic of
transcendental analysis, the infallible method of astronomy, without
which it could never have compassed the large conclusions of the
"Mecanique Celeste." In his "Protogaea," published in 1693, he laid
the foundation of the science of Geology. From his observations, as
Superintendent of the Hartz Mines, and those which he made in his
subsequent travels through Austria and Italy,--from an examination
of the layers, in different localities, of the earth's crust, he
deduced the first theory, in the geological sense, which has ever
been propounded, of the earth's formation. Orthodox Lutheran as he
was, he braved the theological prejudices which then, even more than
now, affronted scientific inquiry in that direction. "First among men,"
says Flourens, "he demonstrated the two agencies which successively
have formed and reformed the globe,--fire and water." In the region
of metaphysical inquiry, he propounded a new and original theory of
Substance, and gave to philosophy the Monad, the Law of Continuity,
the Preestablished Harmony, and the Best Possible World.

Born at Leipzig, in 1646,--left fatherless at the age of six years,--
by the care of a pious mother and competent guardians, young