GLASS UNIVERSE EB

Dava Sobel

• Publisher: Fourth Estate
• Year: 2016
• Print ISBN: 9780008207038
• eBook ISBN: 9780007548194
• Topic: Physical Sciences
• Subtopic: North American History

AN OBSERVER BOOK OF THE YEAR

'A peerless intellectual biography. The Glass Universe shines and twinkles as brightly as the stars themselves' The Economist

#1 New York Times bestselling author Dava Sobel returns with a captivating, little-known true story of women in science

In the mid-nineteenth century, the Harvard College Observatory began employing women as calculators, or "human computers," to interpret the observations their male counterparts made via telescope each night. As photography transformed the practice of astronomy, the women turned to studying images of the stars captured on glass photographic plates, making extraordinary discoveries that attracted worldwide acclaim. They helped discern what the stars were made of, divided them into meaningful categories for further research, and even found a way to measure distances across space by starlight .

Elegantly written and enriched by excerpts from letters, diaries,
and memoirs, The Glass Universe is the hidden history of a group of remarkable women whose vital contributions to the burgeoning field of astronomy forever changed our understanding of the stars and our place in the universe.

PART ONE

The Colors of Starlight

I swept around for comets about an hour, and then I amused myself with noticing the varieties of color. I wonder that I have so long been insensible to this charm in the skies, the tints of the different stars are so delicate in their variety. … What a pity that some of our manufacturers shouldn’t be able to steal the secret of dyestuffs from the stars.

—Maria Mitchell (1818–1889)
Professor of Astronomy, Vassar College

The white mares of the moon rush along the sky

Beating their golden hoofs upon the glass heavens

—Amy Lowell (1874–1925)
Winner of the Pulitzer Prize for Poetry

CHAPTER ONE

Mrs. Draper’s Intent

THE DRAPER MANSION, uptown on Madison Avenue at Fortieth Street, exuded the new glow of electric light on the festive night of November 15, 1882. The National Academy of Sciences was meeting that week in New York City, and Dr. and Mrs. Henry Draper had invited some forty of its members to dinner. While the usual gaslight illuminated the home’s exterior, novel Edison incandescent lamps burned within—some afloat in bowls of water—for the amusement of the guests at table.

Thomas Edison himself sat among them. He had met the Drapers years ago, on a camping trip in the Wyoming Territory to witness the total solar eclipse of July 29, 1878. During that memorable interlude of midday darkness, as Mr. Edison and Dr. Draper executed their planned observations, Mrs. Draper had dutifully called out the seconds of totality (165 in all) for the benefit of the entire expedition party, from inside a tent, where she remained secluded, blind to the spectacle, lest the sight of it unnerve her and cause her to lose count.

The red-haired Mrs. Draper, an heiress and a renowned hostess, surveyed her electrified salon with satisfaction. Not even Chester Arthur in the White House lighted his dinner parties with electricity. Nor could the president attract a more impressive assembly of science’s luminaries. Here she welcomed the well-known zoologists Alexander Agassiz, down from Cambridge, Massachusetts, and Spencer Baird, up from the Smithsonian Institution in Washington. She introduced her family friend Whitelaw Reid of the New York Tribune to Asaph Hall, world famous for his discovery of Mars’s two moons, and to solar expert Samuel Langley, as well as to the directors of every prominent observatory on the Eastern Seaboard. No astronomer in the country could refuse an invitation to the home of Henry Draper.

It was her home, in fact—her childhood home, built by her late father, the railroad and real estate magnate Cortlandt Palmer, long before the neighborhood became fashionable. Now she made certain the house suited Henry as perfectly as she did, with its entire third floor converted into his machine workshop, and the loft over the stable repurposed as his chemical laboratory, which he reached via a covered walkway connected to the dwelling.

She had barely heeded the stars before meeting Henry, any more than she regarded grains of sand at the shore. He was the one who pointed out to her their subtle colors and differences in brightness, even as he whispered his dream of abjuring medicine for astronomy. If she feigned interest at first to please him, she had long since found her own passion, and proved a willing partner in observation as in marriage. How many nights had she knelt by his side in the cold and dark, spreading foul-smelling emulsion on the glass photographic plates he used with his handcrafted telescopes?

A glance at Henry’s plate confirmed he had not touched the banquet fare. He was fighting a cold, or perhaps it was pneumonia. A few weeks earlier, while he and his old Union Army pals were hunting in the Rocky Mountains, a blizzard had struck and stranded them above the timberline, far from shelter. The chill and exhaustion of that exposure still plagued Henry. He looked terrible, as though suddenly an old man at forty-five. Yet he continued chatting amiably with the company, explaining anew, each time anyone asked, how he had generated steady current for the Edison lamps from his own gas-powered dynamo.

Soon she and Henry would be leaving the city for their private observatory upriver at Hastings-on-Hudson. Now that he had finally resigned his professorship on the faculty at New York University, they could devote themselves to his most important mission. In their fifteen shared years, she had seen his landmark achievements in stellar photography win him all manner of acclaim—his 1874 gold medal from Congress, his election to the National Academy of Sciences, his status as a fellow of the American Association for the Advancement of Science. What would the world say when her Henry resolved the seemingly intractable age-old mystery of the chemical composition of the stars?

After bidding the guests good-night at the close of that glittering evening, Henry Draper took a hot bath, then took to his bed, and stayed there. Five days later he was dead.

• • •

IN THE OUTFLOW OF CONDOLENCES following her husband’s funeral, Anna Palmer Draper drew some comfort from a correspondence with Professor Edward Pickering of the Harvard College Observatory, one of the guests at the Academy gathering the night of Henry’s collapse.

“My dear Mrs. Draper,” Pickering wrote on January 13, 1883, “Mr. Clark [of Alvan Clark & Sons, the preeminent telescope makers] tells me that you are preparing to complete the work in which Dr. Draper was engaged, and my interest in this matter must be my excuse for addressing you regarding it. I need not state my satisfaction that you are taking this step, since it must be obvious that in no other way could you erect so lasting a monument to his memory.”

This was indeed Mrs. Draper’s intention. She and Henry had no children to carry on his legacy, and she had resolved to do so on her own.

“I fully appreciate the difficulty of your task,” Pickering continued. “There is no astronomer in this country whose work would be so hard to complete as Dr. Draper’s. He had that extraordinary perseverance and skill which enabled him to secure results after trials and failures which would have discouraged anyone else.”

Pickering referred specifically to the doctor’s most recent photographs of the brightest stars. These hundred-some pictures had been taken through a prism that split starlight into its spectrum of component colors. Although the photographic process reduced the rainbow hues to black and white, the images preserved telltale patterns of lines within each spectrum—lines that hinted at the stars’ constituent elements. In after-dinner conversation at the November gala, Pickering had offered to help decipher the spectral patterns by measuring them with specialized equipment at Harvard. The doctor had declined, confident that his new freedom from teaching at NYU would allow him time to build his own measuring apparatus. But now all that had changed, and so Pickering repeated the offer to Mrs. Draper. “I should be greatly pleased if I might do something in memory of a friend whose talents I always admired,” he wrote.

“Whatever may be your final arrangements regarding the great work you have undertaken,” Pickering said in closing, “pray recollect that if I can in any way advise or aid you, I shall be doing but little to repay Dr. Draper for a friendship which I shall always value, but which can never be replaced.”

Mrs. Draper rushed to reply just a few days later, January 17, 1883, on notepaper edged in black.

“My dear Prof. Pickering:

“Thanks so very much for your kind and encouraging letter. The only interest I can now take in life will be in having Henry’s work continued, yet I feel so very incompetent for the task that my courage sometimes completely fails me— I understand Henry’s plans and his manner of working, perhaps better than anyone else, but I could not get along without an assistant and my main difficulty is to find a person sufficiently acquainted with physics, chemistry, and astronomy to carry on the various researches. I will probably find it necessary to have two assistants, one for the Observatory and one for the laboratory work, for it is not likely that I will find any one person with the varied scientific knowledge that was peculiar to Henry.”

She was prepared to pay good salaries in order to draw the most qualified men as assistants. She and her two brothers had inherited their father’s vast real estate holdings, and Henry had managed her share of the fortune to excellent effect.

“It is so hard that he should be taken away just as he had arranged all his affairs to have time to do the work he really enjoyed, and in which he could have accomplished so much. I cannot be reconciled to it in any way.” Nevertheless she hoped to get the work running as soon as possible under her own direction, and “then, when I can buy the place at Hastings where the Observatory is, to do so.”

Henry had built the facility on the grounds of a country retreat owned by his father, Dr. John William Draper. The elder Dr. Draper, the first physician in the family to mix medicine with active research in chemistry and astronomy, had died a widower the previous January. His will bequeathed his entire estate to his beloved spinster sister, Dorothy Catherine Draper, who had founded and run a girls’ school in her youth to finance his education. It was not yet clear whether Henry’s widow would win control of the Hastings property as she wished, and move Henry’s Madison Avenue laboratory there, and endow the site as an institution for original research, to be named the Henry Draper Astronomical and Physical Observatory.

“As long as I could I should keep the direction of the institution myself,” she told Pickering. “It seems the only suitable memorial I can erect to Henry, and the only way to perpetuate his name and his work.”

At the end she entreated Pickering’s counsel. “I am so unusually alone in the world, that without feeling that those friends who were interested in Henry’s work would advise me, I could not do anything.”

Pickering encouraged her to publish her husband’s findings to date, since it might take her a long time to add to them. Once again he extended his offer to examine the glass photographic plates on the measuring machine at Harvard, if she would be so good as to send him some.

Mrs. Draper agreed but thought it best to deliver the plates in person. They were small objects, only about an inch square each.

“I may be obliged to go to Boston in the course of the next ten days to attend to some business matters with one of my brothers,” she wrote on January 25. “If so I could take the negatives with me and by going to Cambridge for part of a day, if it was convenient for you, could look over the pictures with you, and see what you think of them.”

As arranged, she reached Summerhouse Hill above Harvard Yard on Friday morning, February 9, accompanied by her husband’s close friend and colleague George F. Barker of the University of Pennsylvania. Barker, who was preparing a biographical memoir of Henry, had been the Drapers’ houseguest at the time of the Academy dinner. Late that night, when Henry was seized with a violent chill while bathing, it was Barker who helped lift him from the tub and carry him to the bedroom. Then he bid the Drapers’ neighbor and physician Dr. Metcalfe, another dinner guest, to return to the house immediately. Dr. Metcalfe diagnosed double pleurisy. Although Henry of course received the most tender nursing—and showed some brief promise of improvement—the infection spread to his heart. On Sunday the doctor noted the signs of pericarditis, which precipitated Henry’s death at about four o’clock Monday morning, the twentieth of November.

• • •

MRS. DRAPER HAD VISITED OBSERVATORIES with her husband in Europe and the States, but she had not set foot inside one in months. At Harvard, the large domed building that housed the several telescopes doubled as the director’s residence. Both Professor and Mrs. Pickering ushered her into the pleasant rooms and made her feel welcome.

Mrs. Pickering, née Lizzie Wadsworth Sparks, daughter of former Harvard president Jared Sparks, did not aid her...

Table of contents

• Cover
• Title Page
• Copyright
• Dedication
• Contents
• Preface
• PART ONE: The Colors of Starlight
• PART TWO: Oh, Be A Fine Girl, Kiss Me!
• PART THREE: In the Depths Above
• Picture Section
• Appreciation
• Sources
• Some Highlights in the History of the Harvard College Observatory
• Glossary
• A Catalogue of Harvard Astronomers, Assistants, and Associates
• Remarks
• Bibliography
• Also by Dava Sobel
• About the Author
• About the Publisher