34 THE WORK OF THE STOCK EXCHANGE superstructural city life built about it, the parent market place of the city steadily performed its less striking but more basic economic functions. The daily exchange of goods among unremembered merchants, the influx of imports, and the out- flow of exports, went quietly on. While on the Acropolis Pericles was planning a greater Athenian empire, while Phidias was carving the white loveliness of the reliefs on the Parthenon, or while Plato was discoursing of immortality in the Academy, the purchase and sale of goods proceeded steadily in the Pireeus—in the main unremarked by the historians and unsung by the poets, and yet fundamentally vital to the glory and power of the Athenian state. On the other hand, once its market place had decayed, the city which so often scorned it, so often viewed it as an objec- *ionable congregation of noisy sharpers and rascals, was smit- ten as if with a palsy. Indeed, the ever-shifting routes of trade and the stern competition between market places have left a wake across the world of ruined cities, of abandoned or decayed communities, of rotting harbors, whence in better days intrepid tradesmen went down to the sea in ships to satisfy the clamor of the market place for the goods of distant lands and strange peoples. The mere passage of time has not altered this inexorable economic law. The great cities of the present day exist at the sufferance of supply and demand. As market places they arose, and as market places they will continue to prosper, or else go the way of Venice and Carthage. America is still too young a nation to realize the full significance of her market places. There seems no particular limit set against the continual growth of her cities. Yet we too must cherish our market places, lest in the end we learn the bitter lesson which was forced upon the Pheenicians of Tyre or the Greeks of Corinth. Evolution of the Market Place.—The earliest and simplest markets were formed by the congregation in one place of buyers and sellers, driven together by the economic necessities