cavalry; they were chiefly used to garrison fortified places and defend cities. The cavalry were far more important at Athens than at Sparta. Every tribe supplied a hundred horsemen, and altogether these formed two divisions of five hundred men, commanded by the Hipparchs. As the State did not provide the horses, but expected the soldiers to procure and feed their own, this service was a very expensive one, and consequently was only undertaken by the first two classes. These cavalry regiments, which were the pride of the Athenian citizens, were exercised in time of peace also, and from time to time inspected by the Council of Five Hundred; we have already mentioned that the cavalry played an important part at the Panathenaic procession. In ancient times the army was commanded in time of war by the king, and afterwards by the archon as long as there was only one; when there were nine archons this duty fell to one of them, called the Polemarch. After the reforms of Cleisthenes, it became customary for each tribe to elect a general (στρατηγός), and for the chief command in time of war to fall to all these generals in turn, each commanding for a day. Next came the “Taxiarchs,” and the two “Hipparchs,” and ten “Phylarchs,” but nearly all these offices lost their importance, as did also the military organisation of the citizens, when the [Illustration: FIG. 167.] mercenary system was introduced. This began as early as the time of the Peloponnesian war, and gradually gained ground. Originally they hired troops from foreign nations of a kind which were wanting in their own army; thus, javelin throwers were brought from Rhodes, and archers from Crete, but in the course of the fourth century the actual Hellenic population, and in particular that of Attica, became more and more unwarlike, and as the princes of Macedonia and other non-Hellenic states began to form standing armies of well-disciplined mercenary troops, the Hellenic republics were forced to follow this example as their own military power diminished. This mercenary system did a great deal to undermine the independence of Greece, and facilitate its subjection under the Macedonian dominion. Even in the time of the Peloponnesian war, the Arcadians were willing to fight for anyone who would pay them, against their own countrymen; in the expedition of the Ten Thousand, they formed an important part of the troops of [Illustration: FIG. 168.]