As Hawksworth walked past, self-consciously trying to absorb a sense of place, the gardeners appraised him mutely with quick, flicking sweeps of their eyes. But none made any move to acknowledge his presence. The sun burned through the almost limitless sky, whose blue was polished to a ceramic glaze, and the air was clean and perfumed with nectar. The garden lay about him like a mosaic of naturalism perfected. Through the conspicuous hand of man, nature had been coerced, or charmed, to exquisite refinement. The gravel pathway ended abruptly as he reached the pond's far shore, terminated by a row of marble flagstones. Beyond lay geometrical arbors of fruit-laden trees-- mangoes, apples, pears, lemons, and even oranges. Hawksworth tightened his new robe about his waist and entered one of the orchard's many pathways, marveling. I've found the Garden of Eden. The rows of trees spread out in perfect regularity, squared as carefully as the columns of the palace verandas and organized by species of fruit. As he explored the man-made forest, he began to find its regularity satisfying and curiously calming. Then in the distance, over the treetops, a high stone wall came into view, and from beyond could be heard the splashes of men laboring in the moat. He realized he had reached the farthest extent of the palace grounds. As he neared the wall, the orchard gave way to an abandoned clearing in whose center stood a moss-covered marble stairway projecting upward into space, leading nowhere. The original polish on its steps was now buried in layers of dust and overgrowth. Was there once a villa here? But where's the . . . ? Then he saw the rest. Curving upward on either side of the stairway was a moss-covered band of marble over two feet wide and almost twenty feet in length, concave, etched, and numbered. It's some sort of sundial. But it's enormous. He turned and realized he was standing next to yet another stone instrument, a round plaque in red and white marble, like the dial of a water clock, on which Persian symbols for the zodiac had been inscribed. And beyond that was the remains of a circular building, perforated with dozens of doorways, with a tall pillar in the middle. Next to it was a shallow marble well, half a hemisphere sunk into the ground, with precise gradations etched all across the bottom. Hawksworth walked in among the marble instruments, his astonishment growing. They were all etched to a precision he had never before seen in stone. This observatory is incredible. The sundial is obvious, even if the purpose of the stairway over its center isn't. But what's the round vertical plaque? Or that round building there, and the curious marble well? Could those be some sort of Persian astrolabe, like navigators use to estimate latitude by fixing the elevation of the sun or stars?