The Glass Universe: The Hidden History of the Women Who Took the Measure of the Stars. Дава Собел

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СКАЧАТЬ some harm, for these are disappointed persons, even in some cases mortified—though in fact without cause.” She urged Pickering to assess a new crop of astronomers whose projects she could assist.

      All this time, Miss Bruce’s lavish gift to Harvard still lay in the bank unused, awaiting the arrival of the lens disks from Paris. Pickering’s queries to the glassmaker, Mantois, went unanswered, as did letters and cablegrams sent from the Clarks. After eighteen months, Miss Bruce denounced “that miserable laggard Mantois,” and wished she could confront him in person, confident that her command of French was “probably at least as good as his.”

      In the spring of 1891, nearly two years after Pickering placed the lens order, he discovered to his distress that Mantois had not even begun to form the glass.

      “I shall be only less glad than you when the disc arrives and Clark finds it satisfactory,” Miss Bruce sympathized on April 9. “Let your patience hold out a little longer—another two years or so—and what are two years in the calculations of an astronomer?”

      • • •

      WILLIAM H. PICKERING, the designated first director of Harvard’s southern observatory, reached Arequipa in January 1891. He viewed his arrival as the foundation of a dynasty. His brother already ruled the familiar realm of the northern skies from Cambridge, while here below the equator William would explore the lesser known heavens and establish his own reputation. True, he supervised only two astronomical assistants for the moment, but he presumed the need for a larger staff in Peru would become apparent as soon as the rainy season ended and observations commenced.

      William first had to lease or buy land in the area the Bailey brothers had scouted. Solon and Ruth Bailey were packing to go home, vacating their rented house in Arequipa so the Pickerings could move into it. William had come accompanied by his wife, Anne; their two toddlers, Willie and Esther; Anne’s widowed mother, Eliza Butts of Rhode Island; plus a nurse. To accommodate his family in accord with his sense of mission, he treated the $500 sum he had been allotted for land acquisition as merely the down payment on an expensive property. There he began construction of several permanent buildings for the telescopes, and also a commodious hacienda, complete with servants’ quarters and stable. In February, after only a few weeks in residence, William cabled Edward, “Send four thousand more.”

      By Western Union and stern letters in longhand, Edward tried to make William hew to a stricter economy. In addition, the older brother repeatedly pressed the younger to get busy taking pictures. The Henry Draper Memorial hungered for more photographs of southern stellar spectra. Why did William not make use of the Bache telescope already set up on-site, even as he oversaw the erection of shelters for the three additional telescopes he had brought to Peru? (Over a comparable period during the first expedition in 1889, Bailey had returned some four hundred plates.) In April, William finally obeyed, but still delayed sending the photographs to Cambridge. By August, Edward complained in exasperation, “I am very glad that you have 500 plates but very sorry that they are not here. I am very anxious lest some mistake regarding instructions may make them worthless.”

      William had never been happier, never enjoyed better seeing—the astronomer’s term for atmospheric conditions. He loved the clear, still mountain air of the Andes that enabled him to resolve unprecedented fine detail on the surfaces of the Moon and planets. Although the solar system was not the focus of any Harvard program planned for Peru, the planets now absorbed William’s attention almost to the exclusion of photometry and spectroscopy. Despite his early devotion to photographic technique, William backslid into visual observing at Arequipa. The 13-inch Boyden telescope, with which he photographed the eclipse in California, had suffered some damage to its clock drive on the journey south, rendering it temporarily unfit for long-exposure photography. Until new parts were in place, William felt free to savor the view through the instrument. It had a reversible lens that rendered it equally fit for the eye or the camera. Even after the needed repairs to the 13-inch were completed, and it stood ready to photograph the spectra of the brightest southern stars, William preferred to peer through its eyepiece and sketch the landscape of Mars.

      While William neglected his duty in Peru, Mantois in Paris honored other lens orders ahead of Harvard’s. Miss Bruce deputized J. Cleaves Dodge, an old family friend living in France, to visit the glazier in the hope of rousing him to action on her telescope.

      “We are not in luck,” Miss Bruce told Pickering on October 1, 1891, “decidedly not— Accept my condolences. Here is another cause of delay— Before you see all those discs you will have discovered your first grey hair and I! I shall be in cool repose in Greenwood [Cemetery]. But read Mr. Dodge’s letter.”

      The enclosure described a cordial, half-hour conversation in which M. Mantois explained to Mr. Dodge “the mysteries of Crown and Flint glass, which to manufacture and to manipulate, as he seems to do, one must be a real alchemist.” This was hardly an exaggeration. Telescope lenses required glass made from the highest-quality materials, mixed according to secret recipes, and heated for weeks at temperatures above one thousand degrees in guarded foundries. The terms “crown” and “flint” distinguished the two basic types of glass by the added quantities of lead in the latter. Used alone, either crown glass or flint glass yielded lenses that brought different wavelengths of light to different focal points, creating a jumble of color distortion known as chromatic aberration. United, however, crown and flint corrected each other. As Joseph von Fraunhofer demonstrated in the early nineteenth century, a “doublet,” formed by a convex lens of crown glass paired with a concave complement of flint glass, could bring the focal points into better alignment.

      “The trouble in the making of the lenses,” Dodge’s report to Miss Bruce continued, “seems to be the numerous accidents that occur in the firing and baking of the very best specimens, and which no human intelligence can foretell.” Mantois had lost months to bad luck with a 40-inch lens commissioned by another university and could not yet say for certain when he might satisfy Harvard, willing though he was. Dodge reproduced a verbatim recital of the man’s plight: “M. Mantois said, ‘You see I am as interested as anyone in the completion of the work, for I am not paid anything till it is all finished, but I can only send that which is perfectly satisfactory. Besides I am constantly in a great state of anxiety as to the baking of the molds; I have tubes connected with my bed to warn me at night if the fires are cooling; and the falling asleep of one of the watchmen may cost me no end of trouble and expense.’” Dodge left Mantois’s establishment convinced that no other career in manufacturing “is attended with more chances of failure than this one of glazier for telescopes.”

      • • •

      HAVING CLASSIFIED TEN THOUSAND STARS, Mina Fleming turned her organizational gift to the arrangement of the ever-multiplying glass plates. The myriad photographs filled many wooden chests shelves and cupboards in both the computing rooms and the library. She imagined they would soon exceed all available space in the observatory building. In the interim she filed them by telescope and by type—the chart plates that mapped each section of the sky, the group spectra, the individual bright spectra, the star trails, and so on—each one in a brown paper envelope, each envelope labeled by number, date, and other identifying details, all of which were repeated on index cards in a card catalogue. Rather than pile the plates in columns, she stood them on edge for easy access. Reason to revisit one or another stored plate arose daily as the assistants examined, measured, discussed, and performed computations upon each new batch of photographs. When, for example, Mrs. Fleming spotted a spectrum that struck her as characteristic of a variable star, she did not need to wait for future observations to confirm her hypothesis. The evidence of the past would bear her out in the now. She had only to consult her records to see which photographs included that portion of the heavens, then pull the relevant plates from the stacks and compare the star’s current state with all its previous manifestations.

      “So you have, ready to hand and for your immediate use,” Mrs. Fleming pointed out in a summary of СКАЧАТЬ