Free First Light: The Search for the Edge of the Universe by Richard Preston

to within a hundredth of an inch, no matterwhere the telescope points, and thus keeps the stars in focus. “I was given a job nobody thought could be done,” Mark Serrurier told me. “That’s where I got my satisfaction.”
    During the summer of 1936, work crews blasted and dug a circle of holes in the fern meadow. Caltech students hauled rock out of the holes by hand, using wheelbarrows. The dome was designed by committee. Russell Porter, an artist, explorer, and amateur telescope maker, may have elaborated some of the Art Deco decoration on the dome, although even these details seem to have been worked out by the committee. Porter noticed that the dome’s size was within two feet of the diameter and height of the Pantheon in Rome. The committee had evidently not planned that.
    The Westinghouse Electric and Manufacturing Company, in South Philadelphia, cast and machined the tube, the yoke, and the horseshoe bearing. A workman named William Ladley put the last rivet into the Serrurier Truss, before a crowd of dignitaries in South Philadelphia, including Albert Einstein. Tube, yoke, and horseshoe bearing traveled to California through the Panama Canal, chained to the deck of a freighter. Those parts were assembled on the mountain, inside the dome, under the direction of a master engineer named Byron Hill, who later became the observatory superintendent. I found Byron Hill in a double-sized mobile home on top of a hill in Tuolumne, California, with his wife, who was in poor health. He spends his mornings feeding birds on the patio and drinking coffee, and does not spend a lot of time congratulating himself on what he did to improve the vision of the species. “I get a little older every day,” Byron Hill said. “I object to it.” During his days as superintendent of the observatory, the astronomers sometimes referred to Palomar Mountain as Byron’s Hill. They regarded him as a tough customer; he used to wear a leather jacket and aviator’s glasses. He once threw an astronomer out of the dining room for wearing Bermuda shorts—“His legs
shocked
the housekeeper,” he explained to me. On another occasion a night assistant parked his truck inside the Hale dome, where Byron thought it did not belong. Byron fitted a chain around the truck, hoisted the truck up to the top of the dome, and let it dangle next to the Hale Telescope. About the tube, yoke, and horseshoe bearing he said, “The things fitted together beautifully.”
    The mirror-blank was cast at Corning Glass Works, in Corning, New York. George McCauley, a master of Pyrex, directed the work. McCauley was a taciturn man. Asked how he planned to cast the glass, he said, “It will be no different than making a bean pot, except in the methods employed.” The methods included building an igloo-shaped oven and casting a series of disks inside the igloo, in molds that resembled waffle irons. McCauley started with small disks and worked his way up to two hundred inches. His methods produced a mess during the first casting of a two-hundred-inch disk, when pieces of the mold broke off and floated away in a mulligatawny of hot Pyrex. Asked what he planned to do next, McCauley snapped, “We’ll just make a new disk.” On December 2, 1934, McCauley’s men ladled about forty buckets of white-hot Pyrex into another waffle mold. The Pyrex was thick stuff and oozed out of the buckets in glops, like refrigerated honey. McCauley kept the melt in the oven for ten months, gradually cooling it, letting the glass anneal.
    When McCauley opened the cold oven, he saw that he had made the world’s largest monolithic piece of glass. It had a hole in the center, like a doughnut. Corning engineers encased the disk in a steel shell and stood it upright on a flatcar, to be drawn by a steam locomotive to California. For more than two weeks the telescope train crossed the United States, often at speeds of five miles an hour. Every time the train stopped, armed guards dived underneath