If architecture is the most significant and enduring portion of the history of a people, a sure index of their mental state and social progress, plastic and graphic art are also striking exponents of their national character. The beautiful marble which forms the cliffs and coasts of Greece, notwithstanding its homogeneous transformation, betrays by veins and fossils its sedimentary formation. And so Hellenism, although it may be homogeneous, nevertheless betrays its secondary origin, and the sedimentary material which constitutes its groundwork. The rudimentary vestiges bear the same impress in Assyria, Egypt, and even among savage races; but the Greeks ignored the origin of these, rose above their hieratical meanings, and stamped all creations with their own peculiar manner. Their system of polychromy was the richest in antiquity, combining the lapidary style brought by the Dorians from Egypt, and the more brilliant tints which were attained when the Ionic mind penetrated Doric matter, and transfigured it with all the glories of Asiatic color. As Homer describes only progressive actions, so his great race executed nothing but what was bounded by the delicate lines of grace. The Parthenon has generally been regarded as being exactly rectilinear; but Penrose has recently demonstrated, by careful admeasurements, that probably there is not a straight line in the building. All is embraced within mathematical curves, accurately calculated, and designed to correct the disagreeable effect produced on a practiced eye by perfectly straight lines. Taken as a whole, this work is sublimely grand, and, in its minutest details, it is perfectly wonderful. When unmutilated, it was the aggregate of all artistic worth, and yet remains, of its age, the chief emblem of intellectual majesty.