In tracing the intellectual progress of mankind and the gradual extension of cosmical views, the period of the Roman universal Empire presents itself as one of the most important epochs. We now for the first time find all those fertile regions of the globe which surround the basin of the Mediterranean connected in a bond of close political union, which also comprehended extensive countries to the eastward. I may here appropriately notice, that this political union gives to the picture which I endeavour to trace, (that of the history of the contemplation of the universe), an objective unity of presentation. Our civilization, i. e. the intellectual development of all the nations of the European Continent, may be regarded as based on that of the dwellers around the Mediterranean, and more immediately on that of the Greeks and the Romans. That which we term, perhaps too exclusively, classical literature, has received this denomination through men's recognition of the source from whence our earliest know ledge has largely flowed, and which gave the first impulse to a class of ideas and feelings most intimately connected with the civilization and intellectual elevation of a nation or a race. We do not by any means regard as unimportant the elements of knowledge, which, flowing through the great current of Greek and Roman cultivation, were yet derived in a variety of ways from other sources—from the valley of the Nile, Phœnicia, the banks of the Euphrates, and India; but even for these we are indebted, in the first instance, to the Greeks, and to Romans surrounded by Etruscans and Greeks.