I Must now deal with the use of machines in war, which means siege warfare and naval warfare. The developments which I sketched in the first two lectures were due to the Macedonian and the Asiatic; but the story of machines—siege trains and ships—is largely one of Greek brains, though often in Macedonian service. This illustrates both the driving power of the Macedonian and the tremendous pressure exerted by war, for, apart from military needs, Greeks invented next to nothing in the way of machinery; the Greek mind, perhaps happily for itself, did not work that way.

It had been very difficult in classical Greece to take a walled city. They had some sort of battering ram—Pericles used one at Samos; scaling ladders were known, and tunnelling under the wall; a mound of earth might be raised against the wall, as the Spartans did at Plataea. But speaking generally, you either tried to starve a city out, or relied on your friends inside; a large part of Aeneas' military manual, written about 350 for commanders of besieged cities, is taken up with devices to circumvent the friends of the besiegers inside the wall, and even Philip secured nearly every city he took through treachery. But the later Assyrian kings had known more than this; beside rams, they had used towers to raise their archers to the level of the battlements, and they had regularly taken walled cities in a way which Greeks before Philip's time were quite unable to do.