Such in origin was the Canaanite branch of the Western Semites, and it may be worth while to glance for a moment at the main features of their culture as revealed by excavation in Palestine.[7] One thing stands out clearly: they revolutionized conditions of life in Canaan. The rude huts of the first settlers were superseded by houses of brick and stone, and, in place of villages, cities rose surrounded by massive walls. The city-wall of Gezer was more than thirteen feet thick and was defended by strong towers. That of Megiddo was twenty-six feet in thickness, and its foot was further protected by a slope, or _glacis,_ of beaten earth. To secure their water-supply in time of siege, the arrangements were equally thorough. At Gezer, for example, a huge tunnel was found, hewn in the solid rock, which gave access to an abundant spring of water over ninety feet below the surface of the ground. Not only had the earlier nomad adopted the agricultural life, but he soon evolved a system of defence for his settlements, suggested by the hilly character of his new country and its ample supply of stone.[8] Not less remarkable is the light thrown by the excavations on details of Canaanite worship. The centre of each town was the high place, where huge monoliths were erected, some of them, when unearthed, still worn and polished by the kisses of their worshippers. At Gezer ten such monoliths were discovered in a row, and it is worth noting that they were erected over a sacred cave of the neolithic inhabitants, proving that the ancient sanctuary was taken over by the Semitic invaders. The religious centres inherited by the Ba'alîm, or local "Lords" of Canaanite worship, had evidently been sanctified by long tradition. In the soil beneath the high places both at Gezer and at Megiddo numbers of jars were found containing the bodies of children, and we may probably see in this fact evidence of infant-sacrifice, the survival of which into later periods is attested by Hebrew tradition. In the cultural remains of these Semitic invaders a distinct development is discernible. During the earlier period there is scarcely a trace of foreign influence, but later on we find importations from both Babylonia and Egypt.