the last stage, as well as in the first, it may be called Babylonia. For purposes of distinction, however, it will be as well to call these three successive stages Chaldæa, Assyria, and Babylonia.

Meanwhile, immediately to the east, a somewhat similar process had been gone through, though here the development was from north to south, the Medes of the north developing a powerful empire in the north of Persia, which ultimately fell into the hands of Cyrus the Great in 546 B.C. He then proceeded to conquer the kingdom of Lydia, in the northwest part of Asia Minor, which had previously inherited the dominions of the Hittites. Finally he proceeded to seize the empire of Babylonia, by his successful attack on the capital, 538 B.C. He extended his rule nearly as far as India on one side, and, as we know from the Bible, to the borders of Egypt on the other. His son Cambyses even succeeded in adding Egypt for a time to the Persian Empire. The oyster-shell of history had accordingly expanded to include almost the whole of Western Asia.

The next two centuries are taken up in universal history by the magnificent struggle of the Greeks against the Persian Empire—the most decisive conflict in all history, for it determined whether Europe or Asia should conquer the world. Hitherto the course of conquest had been from east to west, and if Xerxes' invasion had been successful, there is little doubt that the westward tendency would have continued. But the larger the tract of country which an empire covers—especially when different tribes and nations are included in it—the weaker and less organised it becomes. Within little more than a century of the death of Cyrus the Great the Greeks discovered the vulnerable point in the Persian Empire, owing to an expedition of ten thousand Greek mercenaries under Xenophon, who had been engaged by Cyrus the younger in an attempt to capture the Persian Empire from his brother. Cyrus was slain, 401 B.C., but the ten thousand, under the leadership of Xenophon, were enabled, to hold their own against all the attempts of the Persians to destroy them, and found their way back to Greece.

Meanwhile the usual process had been going on in Greece by which a country becomes consolidated. From time to time one of the tribes into which that mountainous country was divided obtained supremacy over the rest: at first the Athenians, owing to the prominent part they had taken in repelling the Persians; then the Spartans, and finally the Thebans. But on the northern frontiers a race of hardy mountaineers, the Macedonians, had consolidated their power, and, under Philip of Macedon, became masters of all Greece. Philip had learned the lesson taught by the successful retreat of the ten thousand, and, just before his death, was preparing to attack the Great King (of Persia) with all the forces which his supremacy in Greece put at his disposal. His son Alexander the Great carried out Philip's intentions. Within twelve years (334-323 B.C.) he had conquered Persia, Parthia, India (in the strict sense, i.e. the valley of the Indus), and Egypt. After his death his huge empire was divided up among his generals, but, except in the extreme east, the whole of it was administered on Greek methods. A Greek-speaking person could pass from one end to the other without difficulty, and we can understand how a knowledge of the whole tract of country between the Adriatic and the Indus could be obtained by Greek scholars. Alexander founded a large number of cities, all bearing his name, at various points of his itinerary; but of these the most important was that at the mouth of the Nile, known to this day as Alexandria. Here was the intellectual centre of the whole Hellenic world, and accordingly it was here, as we have seen, that Eratosthenes first wrote down in a systematic manner all the knowledge about the habitable earth which had been gained mainly by Alexander's conquests.

Important as was the triumphant march of Alexander through Western Asia, both in history and in geography, it cannot be said to have added so very much to geographical knowledge, for Herodotus was roughly acquainted with most of the country thus traversed, except towards the east of Persia and the north-west of India. But the itineraries of Alexander and his generals must have contributed more exact knowledge of the distances between the various important centres of population, and enabled Eratosthenes and his successors to give them a definite position on their maps of the world. What they chiefly learned from Alexander and his immediate successors was a more accurate knowledge of North-West India. Even as late as Strabo, the sole knowledge possessed at Alexandria of Indian places was that given by Megasthenes, the ambassador to India in the third century B.C.

Meanwhile, in the western portion of the civilised world a similar process had gone on. In the Italian peninsula the usual struggle had gone on between the various tribes inhabiting it. The fertile plain of Lombardy was not in those days regarded as belonging to Italy, but was known as Cisalpine Gaul. The south of Italy, as we have seen, was mainly inhabited by Greek colonists, and was called Great Greece. Between these tracts of country the Italian territory was inhabited by three sets of federate tribes—the Etrurians, the Samnites, and the Latins. During the 230 years between 510 B.C. and 280 B.C. Rome was occupied in obtaining the supremacy among these three sets of tribes, and by the latter date may be regarded as having consolidated Central Italy into an Italian federation, centralised at Rome. At the latter date, the Greek king Pyrrhus of Epirus, attempted to arouse the Greek colonies in Southern Italy against the growing power of Rome; but his interference only resulted in extending the Roman dominion down to the heel and big toe of Italy.

If Rome was to advance farther, Sicily would be the next step, and just at that moment Sicily was being threatened by the other great power of the West—Carthage. Carthage was the most important of the colonies founded by the Phœnicians (probably in the ninth century B.C.), and pursued in the Western Mediterranean the policy of establishing trading stations along the coast, which had distinguished the Phœnicians from their first appearance in history. They seized all the islands in that division of the sea, or at any rate prevented any other nation from settling in Corsica, Sardinia, and the Balearic Isles. In particular Carthage took possession of the western part of Sicily, which had been settled by sister Phœnician colonies. While Rome did everything in its power to consolidate its conquests by admitting the other Italians to some share in the central government, Carthage only regarded its foreign possessions as so many openings for trade. In fact, it dealt with the western littoral of the Mediterranean something like the East India Company treated the coast of Hindostan: it established factories at convenient spots. But just as the East India Company found it necessary to conquer the neighbouring territory in order to secure peaceful trade, so Carthage extended its conquests all down the western coast of Africa and the south-east part of Spain, while Rome was extending into Italy. To continue our conchological analogy, by the time of the first Punic War Rome and Carthage had each expanded into a shell, and between the two intervened the eastern section of the island of Sicily. As the result of this, Rome became master of Sicily, and then the final struggle took place with Hannibal in the second Punic War, which resulted in Rome becoming possessed of Spain and