THE towers of Zenith aspired above the morning mist; austere towers of steel and cement and limestone, sturdy as cliffs and delicate as silver rods. They were neither citadels nor churches, but frankly and beautifully office-buildings. The mist took pity on the fretted structures of earlier generations: the Post Office with its shingle-tortured mansard, the red brick minarets of hulking old houses, factories with stingy and sooted windows, wooden tenements colored like mud. The city was full of such grotesqueries, but the clean towers were thrusting them from the business center, and on the farther hills were shining new houses, homes-they seemed-for laughter and tranquillity.