Many discoveries show that these towns were laid out with a regular 'chess-board' street-plan. That method of town-planning now made definite entry into the European world. No architect or statesman is recorded to have invented or systematically encouraged it. Alexander himself and his architect, one Dinocrates of Rhodes or perhaps of Macedonia, seem to have employed it at Alexandria in Egypt, and this may have set the fashion. Seven years after Alexander's death it recurs at Nicaea in Bithynia, which was refounded by one of Alexander's successors in 323 B.C. and was laid out on this fashion. But no ancient writer credits either the founder or the architect of Alexandria or the founder of Nicaea with any particular theory on the subject. If the chess-board fashion becomes now, with seeming suddenness, the common--although not the universal--rule, that is probably the outcome of the developments sketched in the last chapter. Approximations to chess-board planning had been here and there employed in the century before Alexander. When his conquests and their complicated sequel led, amongst other results, to the foundation of many new towns, it was natural that the most definite form of planning should be chosen for general use. We might, however, wonder whether its adoption was helped by the military character of the generals who founded, and the discharged soldiers who formed the first inhabitants of so many among these towns. Military men are seldom averse to rigidity. It is worth noting, in this connexion, that when chess-board planning came into common use in the Roman Empire, many--perhaps most--of the towns to which it was applied were 'coloniae' manned by time-expired soldiers. So, too, in the Middle Ages and even in comparatively modern times, the towns laid out with rectangular street-plans in northern Italy, in Provence, in the Rhine Valley, are for the most part due in some way or other to military needs.[23] In our own days rectangular planning is a dominant feature of the largest and newest industrial towns. They are adapting a military device to the purposes of an industrial age. [23] Since the invention of artillery, the rectangular street-plan has been regarded by soldiers as useful in defending the streets of a town. Aristotle, however, expressly observes in the _Politics_ that, in street warfare, tortuous lanes were far better than straight avenues for the defence, and he recommends that the rectangular pattern should be adopted only 'in parts and in places', though he does not explain how this would work out (_Politics,_ iv. 11, p. 1330). [Illustration: FIG. 6. GENERAL OUTLINE OF PRIENE. A, B, C. Gates. D, E, F, H, M, P. Temples (see fig. 7). G. Agora, Market. I. Council House, K. Prytaneion. L, Q. Gymnasium. N. Theatre, O. Water-reservoir, R. Race-course.] [Illustration: FIG. 7. PART OF PRIENE AS EXCAVATED 1895-8. (From the large plan by Wiegand and Schrader.)]