Nothing more can be done by the theorists. In this matter it is only you, the astronomers, who can next year perform a simply invaluable service to theoretical physics.
—Albert Einstein to Erwin Freundlich, 1913
THE WORD PHYSICS derives from Ancient Greek and translates quite accurately to “knowledge of nature.” One of the most fundamental of the scientific disciplines, physics aims to understand how the universe conducts itself, how it behaves. Mathematics is a physicist’s third eye. It enables him or her to see beyond the restrictions of ordinary sight when it comes to revolutionary ideas about the cosmos. It opens that gate to an inner and higher perception. Isaac Newton didn’t just see light traveling along a straight path. He envisioned it bending through an angle of 0.87 arc seconds as it passed near the sun, or so his mathematical calculations informed him. This was the famous question he had asked in Opticks. Didn’t bodies act on light at a distance? But when it came to answering this question, Newton was locked into his place in time, third eye or not, in the latter half of the seventeenth century. This intellectual barrier must have been frustrating for someone with his enormous brainpower. He was most capable at describing gravity. He wrote a useful equation to explain how gravity acted, but he had no idea of the mechanism behind it. When Newton died in 1727, his question of light deflection was left in limbo.
As though they were tag-team members from different ages, Einstein had now taken up Newton’s question. But how to find the answer? The science of physics depends on a series of steps before arriving at its conclusions:
1. Using the ability to conceptualize.
2. Encoding this concept in rigorous mathematics.
3. Using the mathematics to make error-free calculations that lead to predictions.
4. Using the senses and devices to make measurements and observations as accurately as possible.
5. Comparing the predictions to what is measured and observed.
In 1704, when Newton published his revolutionary work predicting that the path of light would bend by a measurable amount when passing a large body, he had at his disposal only the first three steps, as did Johann Soldner, in 1804. With his own calculations so close, Soldner essentially performed an independent check on Newton’s work, discovering that Newton was not only a genius for coming up with his concepts, but he could also correctly calculate with them. That’s a skill not always true of a genius. Given Einstein’s place in time, two hundred years down the road from the publication of Opticks, the German physicist could take advantage of all five steps listed above. That a more advanced technology was now at his fingertips was a gift from the gods.
Einstein was already superbly gifted when it came to the first step, that third-eye ability to conceptualize, which he had exhibited from his teenage years when he “rode” a light beam through the vastness of space. For the rigorous math of step 2, he relied on his good friend Marcel Grossman to help him understand the work of four pioneering mathematicians who had preceded them in time.1 For step 3, when he first published his paper, he was simply wrong in those early stages of his calculations. Nature might be infallible, but physicists are not, and even intellects like Newton and Einstein were no exceptions. Newton had arrived at a calculation of 0.87 arc seconds. Even if it were proven wrong, the brilliance it required to envision the bending of light in 1704 can’t be anything but right.
Step 4 is trickier since it depends not just on human senses, but also on current technology. As Charles Perrine and Arthur Eddington stood in their separate huts watching it rain in Brazil in 1912, the art of solar photography had advanced from the day in 1851, when a Prussian daguerreotypist pointed his small telescope at the sun to capture the first photo of the corona. New photographic lenses and filters had been invented over the decades and were now in use. The dry photographic plate was introduced in 1871, replacing the cumbersome wet plate, which had replaced the daguerreotype. The early 1900s had seen the best research telescopes move away from “great refractors” with their large glass lenses to even larger reflectors installed with glass mirrors. Technology was on their side in 1912, even if the weather wasn’t. But it was a dicey endeavor to begin with when you consider that the most fortunate astronomers from the best observatories would likely be blessed with only forty minutes or less to photograph the sun during total eclipses in their entire lifetimes. And that’s if everything went according to plan on an average of a dozen expeditions.
For that last step—comparing the predictions to what is measured and observed—Einstein needed some help. To prove light deflection according to his new theory, he depended on astronomy, a scientific field he had once criticized for its “pedantic accuracy.”
In his enthusiasm for the general theory, Erwin Finlay-Freundlich had become its first great proclaimer, attracting attention to it with his general appeal to observatories in Europe and America. He already had William Campbell and the Lick Observatory aboard, as well as Charles Perrine in Córdoba, Argentina. There was a total eclipse due on April 23, 1913, but no observatory had even considered it. Its path began in the Pacific Ocean south of Japan, cut across the Northwest Territories of Canada and Baffin Island, before ending on the west coast of Greenland. None of these places were easily accessible even if astronomers could set up delicate instruments in such freezing temperatures. But an eclipse coming in the summer of 1914 would lay its path across Norway, Sweden, and a huge chunk of the Russian Empire. Freundlich wanted to observe this eclipse. If he could manage funding, it would be his first. But he felt he needed backup. Astronomers had learned the hard way that the more viewing stations along the path, the better the odds.
In February 1913, Freundlich wrote to Frank Watson Dyson at the Royal Observatory, asking for his participation. Answering quickly, Dyson replied that light deflection was not an incentive for the observatory, despite the British intention to send out several expeditions for that eclipse. “It would be an extremely delicate research to undertake at an eclipse, if not quite beyond present possibilities.” The astronomer royal did refer the request to the Joint Permanent Eclipse Committee, which agreed with him, adding that the members didn’t have the special equipment needed.
Undeterred, Freundlich kept busy. Correspondence fluttered back and forth as he and Einstein discussed plans to have stars photographed during an eclipse. In his reply to Pollok back in September 1911, along with suggesting Jupiter as the large body mass to use, Freundlich had also speculated on photographing stars during the daytime. Einstein was intrigued by this suggestion back then. “Is it really possible to observe stars near the sun in full daylight, i.e. in the absence of a solar eclipse, by means of currently available instruments?” he asked Freundlich. “If this can be achieved, then you shall surely be successful in determining whether the theory is valid.”
By August 1913, with Perrine’s failed attempt in Brazil nearly a year old, Einstein was growing impatient. He had just accepted, in July, a most generous financial offer to move to Berlin and become a professor at the university, as well as the youngest member of the Prussian Academy of Sciences. As an added bonus, he would be made director of the future Kaiser Wilhelm Institute for Physical Research, which was still in the planning stages. He was thirty-four years old. He would not have to teach or carry out any administrative duties. In other words, the position was all riding on his reputation. “The Germans are gambling on me as they would a prize-winning hen,” he had jokingly told a friend. Then he added, “But I don’t know if I can still lay eggs.” This self-doubt may have been his impetus to try anything, even photographing the sun in the daytime, in order to prove himself once more.
August 1913 was an eventful month for Freundlich. In Bonn, Germany, attending the International Union for Cooperation in Solar Research was none other than William Campbell of the Lick Observatory in California.2 Other participants included Campbell’s good friend Frank Watson Dyson from the Royal Observatory, Edward C. Pickering from Harvard, and Arthur Stanley Eddington from Cambridge. After the conference was over, Campbell traveled to Hamburg for a few days and then to Berlin. Since Freundlich was too junior in rank at the Berlin Observatory to be sent to the conference, the Lick director graciously came to him. They discussed the upcoming eclipse preparations for the following year. On the heels of such a successful conference of scientific goodwill, Campbell was pleased with the American-German alliance in testing for the general theory. He would be happy to send Freundlich any successful photographs he would take during the eclipse, provided the Lick Observatory Bulletin would publish Freundlich’s results.3
There were more big changes in the air that August for Freundlich. The last structure of the Berlin Observatory, where he had worked for three years, was being torn down. The new observatory, Berlin-Babelsberg, would open its doors the following spring near Potsdam, where there would be less light pollution. The happiest news was that Freundlich married his fiancée Käte Kirschberg, and the couple planned a honeymoon in the mountains near Zurich. Toward the end of the month, Einstein, who still lived in Zurich until the following spring, wrote again to Freundlich. The astronomer had evidently informed the physicist of Campbell’s visit to Berlin and their discussion of testing for light deflection during the next eclipse, because Einstein responded to Freundlich enthusiastically in a letter:
I am very pleased that you have managed to arouse such great interest in our question regarding a bending of light rays. From a theoretical point of view, the matter is now settled more or less. Privately, I am quite certain that light rays do undergo bending. I am extremely interested in your plan to observe the stars near the sun during daylight. This should be possible unless suspended particles of the order of magnitude of optical wavelengths, which deflect the light only slightly, are present throughout the atmosphere. I am afraid that your plan could founder on that. But you certainly know more about these things than I do.4
At the end of his letter, Einstein congratulated Freundlich on his marriage and added, “I am delighted that I will see you on your honeymoon.” What Käte thought of a no-doubt similar conversation with Einstein on her honeymoon will be left to posterity’s imagination. After the newlyweds met with him in Zurich, they attended a speech that Einstein was scheduled to give later that day about his work in progress. During his talk, he nodded at the tall gentleman seated in the audience next to his petite bride. With his abundant dark hair and wire-rimmed glasses, Freundlich was impressive in stature and demeanor. His being singled out by Einstein that day must have been most gratifying to the young couple. Einstein referred to him as “the man who will be testing the theory next year.”
In October 1913, a restless Einstein, having already experienced the capriciousness of a total eclipse, wrote to astronomer George Ellery Hale. Hale was not just a brilliant solar astronomer known for his study of sunspots, but also a great believer in international cooperation when it came to research. He was then at the Mount Wilson Observatory, which he had founded, outside Los Angeles. Few men knew more about the sun than Hale did. Einstein’s one-page letter included calculations showing light then bending at 0.84 arc seconds.
Three weeks later, Hale replied to Professor Einstein with an apology for taking so long, explaining that he had written to consult William Campbell, director of the Lick Observatory, knowing that Campbell was already interested in the question of light deflection. “He writes me that he has undertaken to secure eclipse photographs of stars near the sun for Doctor Freundlich of the Berlin Observatory, who will measure them in the hope of detecting differential deflections.” Campbell was referring to the eclipse coming in 1914. In his letter, Hale noted that he had recommended that Campbell contact Einstein directly with details. But Hale discouraged Einstein from the idea of photographing stars during daylight hours and listed three reasons: the sky increases in brightness near the sun, atmospheric refraction, and the micrometer—an instrument that measures the apparent diameter of celestial bodies—would not have the range to measure the distance of the star from the sun’s limb. “The eclipse method, on the contrary, appears to be very promising, as it eliminates all of these difficulties,” he wrote.
The eclipse of August 21, 1914, would lay out an ample path of totality across the globe for viewing, even if the first half was inaccessible. The umbral track began in the Beaufort Sea, at Sachs Harbor, Canada. The harbor was named for the ship Mary Sachs, which had run into heavy slush ice less than a year earlier—the vessel was part of the Canadian Arctic Expedition—and had frozen into the sea for the winter. Regardless of that misfortune, the harbor was an impossible place for astronomers to try their luck. Like its predecessor, this eclipse would also cut across Baffin Island and Greenland. It would traverse the Norwegian Sea to reach land at Norway and Sweden, then catch a slice of southern Finland and eastern Estonia before entering western Russia. From there, the path would be most accommodating, stretching down past major Russian cities like Riga, Minsk, Kiev, and Theodosia on the Black Sea. After passing Turkey and the Middle East, it would end at sunset after barely touching India.
A generous track, but with a modest time for viewing. That January, as he often did, Andrew Crommelin had predicted the durations of totality in the Nautical Almanac Circular, a periodical published by the Royal Observatory. Maximum duration would occur fifty miles north of Minsk, where totality would last two minutes and fifteen seconds. All other stations, therefore, could count on a few less seconds. Observatories around the world had begun planning many months in advance. Where to find funding? What instruments to take? Where to set up viewing camps? Who would be team members? Numerous countries, including Norway, Italy, Spain, England, Sweden, France, the United States, and Argentina, began organizing expeditions. Under Perrine’s direction, Argentina was the only country in the Southern Hemisphere to take part. Given the convenient path of the eclipse, some European countries were well represented. Russia would send five expeditions in all.
Freundlich and Walter Zurhellen, from the Berlin-Babelsberg Observatory, along with an optical mechanic named R. Mechau, would go to Theodosia on the Crimean Peninsula. William Campbell and the Lick’s team had chosen a small town near Kiev. The British teams would go to Minsk, Kiev, and Theodosia. Charles Perrine and his mechanic James Mulvey, from the Argentine National Observatory, would also travel to Theodosia and share a viewing station with the Germans and the British. From the Amherst Observatory in Massachusetts, a colorful scientist named David Todd would travel to Russia with plans to chase the eclipse at 120 miles an hour in an airplane. With him would be his wife, Mabel Todd.5 It would be a mixed group. Of all these many teams, only Freundlich, Perrine, and Campbell would test for light deflection.
Having spent years hunting for the ghost planet Vulcan, Perrine and Campbell were now apparently in pursuit of an idea conceived by Einstein. As top-notch astronomers, among the best in the world, they were eager to carry out step 5 for the German physicist: comparing the predictions to what is measured and observed. Perhaps their enthusiasm had something to do with faith in brilliance. After all, Urbain Le Verrier had discovered Neptune with the point of his pen. And Einstein’s pen had written the formula E = mc2.
William Campbell’s tenacity was shaped not just by a difficult childhood, but also by the observatory where he learned and practiced his science. No other observatory in the world would have more involvement in, or a longer commitment to, attempting to test light deflection according to Einstein’s general theory of relativity than did the Lick Observatory. The idea for an observatory sitting high on a mountaintop began in 1873, when an eccentric and aging bachelor named James Lick decided he wanted a superlative observatory in Northern California. His lack of astronomical knowledge was superseded by his tremendous wealth.6
In 1874, Lick set up a trust and endowed it with $700,000, an astonishing figure in those days. It would be $1.2 billion today. He insisted that the observatory would have “a powerful telescope, superior to and more powerful than any telescope yet made, and all the machinery appertaining thereto.” He wanted it built atop Mount Hamilton, a mountain peak near San Jose with an altitude of 4,265 feet. Lick then arranged for the county to carve a five-mile road winding up to the top. He died in 1876 as construction was beginning. Crews would blast seventy thousand tons of rock from the mountain’s top to create a level place on which to build. When the observatory, with the world’s largest telescope installed, was finished in 1888, Lick’s coffin was brought from San Francisco to be reinterred at its base. Two years later, a young astronomer named William Wallace Campbell, age twenty-five, volunteered to work as an assistant. The next year, he was invited to stay permanently on the mountaintop and work on spectroscopy.
Born in 1862 and raised on a farm in Hancock County, Ohio, Campbell was four years old when he lost his father. He and his siblings were soon working in the fields and doing odd jobs to help the family survive. A driven young man, he managed to graduate from the University of Michigan with a degree in civil engineering and a new interest in astronomy. His first job was as professor of mathematics at the University of Colorado, but his passion for astronomy called him back to Michigan to begin teaching this scientific discipline at the university. In 1892, a year after he joined the Lick Observatory, he married a pretty college girl—she had been a student in his math class—and brought her to Mount Hamilton to live. Elizabeth Ballard Thompson could have no way of knowing, as she peered down on the Santa Clara valley below, that she would often travel the world at her husband’s side as he studied eclipses. By 1899, they had three young sons, and by 1901, Campbell had become the Lick’s director.
That unique mountaintop would shape William Campbell for the rest of his life. It was a self-contained community of about fifty people, staff and employees, occupying houses just below the observatory. The director and his family lived in a tiny brick house heated by woodstoves and with a rock-hewn cellar that could store food. A post office, a lumber mill, and a blacksmith shop had been built. At the one-room schoolhouse nestled into the mountainside, a teacher taught the dozen or so students. Church services were held each Sunday in one of the homes, unless a preacher came up the mountain to visit a relative. Services were then moved to the little school. Telephone poles ran up the steep slope, carrying single-grounded wires made of iron to the crank phone on the wall of the director’s kitchen. The world’s first permanently occupied mountaintop observatory was high enough that it was snowed upon in the winters, turning its huge dome into a white castle overlooking the valley below.7
Until 1910, when a gasoline generator was installed in Campbell’s house, he read or wrote letters, and his children did their homework, by kerosene lamplight. In the early years, a stage pulled by two horses lumbered daily up the mountain to deliver the mail and groceries, stopping several times to let the animals rest on the seven-hour round trip. A much larger stage came on Saturday evenings, bringing from the hotel down in San Jose the visitors who had paid a fee to ride up to the observatory. Once inside the dome, they were invited to peer through some of the telescopes. Twice, at the turn of the century, the stage was robbed, depriving its passengers of their money and jewelry. And yet, up that mountain trekked famous astronomers and dignitaries from around the world, including Thomas Edison. Frank Watson Dyson, then senior assistant at the Royal Observatory, came up the mountain to meet Campbell in 1901. He was on his way back from the eclipse in Sumatra, with plans to circumnavigate the globe before returning home to England.
Always fond of Americans, Dyson was impressed with Campbell’s easy manner and the family’s resilience. “We killed a rattlesnake ten yards from Mr. Campbell’s front door,” he wrote home to his wife, “a big one with nine rattles.” With no antivenom available then, all Mount Hamilton boys carried jackknives in their pockets in case of snakebite. “He has three small boys… so you can bet he was glad to kill that snake.” Even the drive back down the mountain didn’t seem to unsettle the Englishman. “The driver was splendid and the way he brought the stage down with his two horses and a precipice on one side and a wall of rock on the other was fine.” It was 1910 before an automobile replaced the stage Dyson had ridden on. A visitor could now make the round trip in two hours, instead of seven by horses.
When he wasn’t chasing an eclipse, Mount Hamilton was Campbell’s world for thirty years. He was a formal man, his speech always proper and refined. He was kind to the mountaintop families, especially the children. He treated the janitor and his family as well as he treated the families of astronomers. But if it was warranted, he could fire an employee on the spot. He was away from the observatory on official business when the 1906 San Francisco earthquake shook his wife and three sons from their beds, knocked bricks from the chimney, and shattered the glass funnel of an oil lamp. With news cut off and with a cloud of gray smoke billowing on the distant horizon, Elizabeth Campbell, Charles Perrine, and others climbed the hill to the observatory and turned a small telescope toward San Francisco and a wall of fire three miles wide.
William Campbell had experience and a reputation for being careful in his research.8 He had been on four previous eclipse expeditions, to India, the US state of Georgia, Spain, and Flint Island, a dot in the middle of the Pacific Ocean. In 1913, he began putting together a team from the Lick Observatory for the upcoming eclipse. He had supported Perrine, his friend and former colleague, by sending Lick’s intra-mercurial camera lenses down to Brazil. He had supported Freundlich and Einstein by offering up his Vulcan plates. A year earlier, he had carefully explained the problem of the plates in a letter to Freundlich: “Your experience with the eclipse plates is about what we had expected: not only is the sun’s image near the edge of the plate, but the aberrations of the camera lens at the edge of the plate are unavoidable; and, further, the clock was regulated to follow the sun and not the stars.” Now he was ready to take up the challenge himself. He would bring his family with him to Russia. He would “follow the stars.”9
Charles Perrine was born in Ohio in July 1867. As is often the case for future astronomers, he was given his first telescope at a young age. A few months before he would graduate from high school, his hometown of Steubenville was caught in the Great Ohio Valley Flood of 1884. In some places, the Ohio River rose thirty-four feet higher than it had ever reached before. Over a hundred houses were soon underwater, while others had been washed away and destroyed. Businesses were submerged, railroad tracks torn up for miles, and, as a sad reminder that would last months, thousands of kegs of nails had been scattered like grain across hundreds of acres of once-fertile farmlands, now lying in mud and rust.
For Steubenville’s youth, faced with such devastation, their futures may have been determined by that flood. Because it would take many months and even years for the towns to recover, it’s hard to imagine what kind of graduation ceremony the Class of ’84 could possibly have had. Two years later, at age nineteen, Perrine packed up and left the Ohio Valley for Alameda, California, across the bay from San Francisco. He may have read in one of his astronomy journals about a new observatory being built on a mountain nearby. It’s also likely he chose Alameda since his mother’s sister was living there at the time. Two years later, in 1888, the Lick Observatory was opened. As it had been for Campbell, on that mountaintop lay Perrine’s destiny. He would evolve into a world-class astronomer.
He secured a job as bookkeeper with Armour & Co., a meatpacking firm in San Francisco. To get to work each day, he took the train and then a ferryboat across the bay. Nights traveling home on the ferry, his eyes would search the skies for meteors or comets. When the brand-new Lick Observatory encouraged amateurs to observe and photograph the January 1, 1889, eclipse for possible publication, Perrine knew it was his chance. He and a professional photographer from Oakland planned a trip north to Mendocino County.10
That the path of totality for this eclipse was only 150 miles north of San Francisco was a gift to the Lick Observatory. This would be its first expedition. Being so conveniently located, the Lick sent out offers to other observatories in the country and Europe, offering to assist them with preparations. While the professional astronomers gave themselves two weeks or more to travel to the viewing sites they had chosen—in the heavy rains that fell that December, the horse-drawn stages were often sunk wheels-deep in mud—it seems that Perrine and his companion left just one day before the eclipse. The report they sent to the observatory said they had checked their watch with the Merchants Exchange Building clock in San Francisco on New Year’s Eve 1888.
Despite the torrential rains before and after, eclipse day was splendid. Using a sixteen-power spyglass, Perrine and his friend succeeded in obtaining eight good negatives. Arriving back in San Francisco on January 2, their watch was now thirty seconds off from the Merchants Exchange clock. They made the time corrections and sent their report and photographs up the mountain to the Lick Observatory. “The corona shone with a soft, silvery light, slightly tinged with blue in the outer streamers,” reads the report that Perrine wrote. What must he have felt at that moment? That first eclipse began a career that would carry him on expeditions around the world and astronomical recognition.
Perrine managed to get a meeting with Edward Holden, the observatory’s first director, and convinced Holden to hire him as secretary. His job was to keep the books, manage the post office, do inventory of equipment and supplies, read and record the time, answer the single phone line, and type and file correspondence to and from staff members. But at least he was inside the door of one of the world’s finest observatories. Nights, he hung out with the astronomers up in the dome, learning all he could from them and forming what would become a long friendship with Campbell. Perrine would learn his craft from a vigilant teacher.
In 1895, the self-taught Perrine—he once said he sold ham to earn a living, referring to his job at the meatpacking plant—became an assistant astronomer at the Lick Observatory. That same year, he discovered his first comet, and then another comet, and then another. When the French Academy of Sciences awarded him the prestigious Lalande Prize for advances in astronomical study just two years later, he had discovered five comets in all and had “rediscovered” two periodic ones. In the spring of 1900, he traveled across the country by train with Campbell to Georgia for his first major eclipse expedition. Within a few more years, he was made president of the Astronomical Society of the Pacific and had discovered two moons of Jupiter. His astrophotography skills were now among the best in the world. In 1905, a few days after Einstein’s special relativity theory was published in Annalen der Physik, Perrine married Bell Smith on the fourth of July. He was thirty-eight years old. After an expedition to Spain with the Campbells to view the eclipse of August 30, the newlyweds went on a world honeymoon, visiting Italy, Switzerland, Germany, France, and England. On their return to California, Bell went to live in Berkeley so she could finish her last year at the University of California.
Charles went back up the mountain to the observatory. Just after 5:00 a.m. on the morning of April 18, 1906, a razor strap hanging on his wall began to swing back and forth. A bookcase moved forward an inch. Windows rattled, and the door swung wide open. His pendulum clock had stopped at 5:12. Perrine volunteered to go to San Francisco and check on the relatives living there. After the stage ride down the mountain, he caught the train from San Jose to Alameda. Across the bay from the destruction, his parents were safe. And so was Bell, in Berkeley. He telegraphed Mount Hamilton: “Folks are fine.” The observatory secretary pinned the message to the bulletin board at the post office, where the mountaintop community could read the good news. The next day, Perrine rode the ferry over to San Francisco. He sent a telegram to Elizabeth Campbell, who was worried about her relatives: “People safely away from danger. Houses are threatened. Greater of San Francisco is gone.” Bell’s graduating class the next month was the only one in the school’s history that didn’t have to take finals, because of the devastation of the 1906 earthquake.
Bell Smith Perrine then went to live with her husband on Mount Hamilton, in one of the small houses not far from the Campbells and their sons. Four years later, in 1909, Charles Perrine became director of the Argentine National Observatory, in Córdoba. He and Bell would leave the mountain and move to the star-filled Southern Hemisphere.
Erwin Freundlich was determined to test for light deflection during the 1914 eclipse. But the old problem of funding again reared its head. His colleagues in the scientific community in Germany had no interest in investing in a project they didn’t understand or believe in, or both, the project being the theory of general relativity. Einstein felt that if the Prussian Academy of Sciences didn’t pitch in—he had by this time accepted its offer to join—that he would dig into his own savings and put up two thousand marks “to start the ball rolling.” The Berlin Academy finally offered some funding, which was still not enough to cover expenses. Freundlich was grateful to be able to borrow parts of telescopes from Perrine, at Córdoba. From them, he had assembled four cameras for his mission. But he needed money for photographic plates, travel, and the various expenditures that an expedition to another country requires.
It was Freundlich’s good luck that a friend had introduced him to Gustav Krupp von Bohlen und Halbach. He was the husband of Bertha Krupp, who had inherited her family’s company at age sixteen when her father, a likely suicide after newspapers exposed him as a homosexual, died in 1902. Kaiser Wilhelm II, a family friend, found a husband for Bertha rather than let the company be run by a woman. Gustav was given the family surname. An old and powerful clan, the Krupp industrial dynasty was known for its manufacture of steel, weapons, and artillery in Europe for over three hundred years. The Krupp company also manufactured U-boats and supplied most of Germany’s need for artillery. Freundlich made a good impression on Gustav and Bertha Krupp, who became the major funders for his expedition to Russia. If there was an irony in the pacifist Einstein’s innocent or deliberate ignorance of where the money was coming from, it wasn’t mentioned.11
Although Dyson was not interested in funding an expedition to test for light deflection for Einstein, the Joint Permanent Eclipse Committee prepared to send three British teams to Russia, from the Royal Observatory, Greenwich, the Imperial College in South Kensington, and the Solar Physics Observatory, which had moved in 1911 from South Kensington to Cambridge. The teams’ main focus would be tests carried out on the sun’s corona and the flash spectrum.12 As is often the case when expeditions visit a foreign country, resident astronomers and observatories help with the governmental permissions, transportation arrangements, viewing stations, and finding local assistants and volunteers. With the British teams going to Russia, the English had been in touch with Johan Oskar Backlund, of the Pulkovo Observatory in Saint Petersburg, for many months. So had Freundlich, Campbell, and Perrine. Backlund had traveled from Paris with Perrine in the fall of 1911, when they had met Freundlich and first heard of Einstein’s new theory.
In January, the august British scientific society known as the Royal Society had asked the Russian government for permission to allow Father Aloysius Cortie and a fellow Jesuit from Stonyhurst College Observatory to be part of the team going to Kiev.13 Cortie met with the Russian ambassador in London, hoping to demonstrate that he was “neither a dangerous nihilist nor a wily proselytizer masquerading as a scientist,” as the Stonyhurst magazine put it. But in May, three months before the eclipse, the Russian Foreign Office denied the Jesuits permission. With time running out, they quickly decided on Hernösand, Sweden, even though early weather reports had indicated that August in Sweden would not bode as well as in Russia. Despite this inhospitality, the Russian government nonetheless, in the interest of science, would give free entry to the other foreigners, free railway shipment for their tons of equipment, and a half-rate fee on all passenger tickets.
After long months of planning, the expeditions from various countries started packing up their instruments and preparing for the journeys to their respective stations. First to embark was Heber Doust Curtis, an astronomer and a Campbell colleague, who left the Lick Observatory on June 15. Curtis had been on other Lick expeditions, including the one to Georgia in 1900 as a volunteer. He would travel ahead with the instruments and equipment to oversee a safe arrival in Kiev. Campbell and the remaining entourage would follow in early July. Curtis had written a review article on general relativity as early as 1911. Complete with a bibliography citing all published sources by others, his was the first paper on this topic to appear in an American astronomical journal.14
Perrine and Mulvey left Córdoba a day later, on June 16, traveling first by train to Buenos Aires. From there, they would catch a steamer to Genoa, Italy, on the initial leg of their journey. Perrine, now the father of two young children, was already a couple decades into his career by this time, having received numerous awards and an honorary doctorate. Being the first astronomer to attempt to test for light deflection according to Einstein’s theory, he was now one of three such astronomers.
Frank Dyson left Liverpool on June 22, on the SS Ascanius. As the astronomer royal, he was bound for Australia and the eighty-fourth meeting of the British Association for the Advancement of Science (BAAS). Arthur Eddington, his former assistant at the Royal Observatory, was traveling on the ship with Dyson to attend the meeting. Eddington had been a year now at Cambridge as Plumian Professor of Astronomy and Experimental Philosophy. When Sir George Darwin died the previous December—he was the second son of the famous evolutionist—Eddington succeeded him. Eddington’s star was rising. Just three months earlier, he had been appointed director of the observatory and had moved with his mother and sister into the lovely Cambridge apartment that came with the job, along with its gardens and lush grounds.
So important were these annual BAAS meetings among scientists of the world—the gatherings were intellectual pleasure cruises of two or three months for physicists, geologists, mathematicians, astronomers, biologists, and so on—that Australia had begun planning five years earlier.15 The Australian Commonwealth gave the group a grant that would amount to two million dollars today. It would cover passage and railway fees for all three hundred members. Along with spreading scientific friendship among countries, the members would sail almost completely around Australia, with stops in various cities for lectures and sightseeing. During the summer of 1914, it seemed as if the greatest scientific minds on the planet were at sea, or soon would be. When Dyson and Eddington set sail on that June day, they were leaving behind what the newspapers referred to as the “Irish problem,” the “suffragette agitation,” and “labour difficulties.” They would come home to an England greatly changed.
It was Sunday morning when Archduke Franz Ferdinand of Austria and his wife Sophie, the duchess of Hohenberg, rode in their 1911 open-style automobile along a street in Sarajevo, then capital of the Austro-Hungarian province of Bosnia and Herzegovina. They had left Vienna by train earlier that morning for a diplomatic visit with the local governor. As the automobile chugged along, a young man stepped out of the crowd lining the street, his arm raised. He was one of a six-member secret cult called the Black Hand, supported by officers in the Serbian military whose current mission was to assassinate the archduke and end Austro-Hungarian rule in Herzegovina and Bosnia. The grenade he tossed at the royal couple bounced off the back of their car and then exploded. The spray of shrapnel injured members of the entourage riding behind them. After arriving at the governor’s residence, where they collected themselves, the archduke and duchess were determined to visit the hospital where an injured officer had been taken.
In what has to be the most fatal decision a chauffeur has ever made, the driver turned down a wrong street. Unaware that the itinerary had changed, he followed the lead cars. Forced to back up slowly in a string of autos, gridlocked, the royal car was an easy target. One might question why, given the earlier attempt on their lives, the royals climbed back into an open-style auto. Nonetheless, the bad luck that day was astonishing, for sitting in a café across the street was another member of the Black Hand. Taking a pistol from his pocket, he left the café and strode over to the open car. He shot Sophie first and then the archduke, who was soon begging for his wife to live for the sake of their children. Sophie’s white dress and the fallen green plumes from the archduke’s hat would be soaked in blood by the time the chauffer finally freed the car and sped away.16 News of the murders spread quickly around the world. Marconigrams were received by governments, newspaper bureaus, and ships at sea. At this time, the assassinations seemed only a single, tragic event in the eyes of the public. After all, it was just an archduke, and where was that little place called Sarajevo?
Telegraphed reports and newspapers gradually began speculating as to what might happen because of the assassinations. But it hadn’t happened yet, and an eclipse cares little for the woes of civilization. Thus, with Curtis gone on ahead, Campbell left San Francisco in early July. He was bringing with him his entire family: his wife Elizabeth, her mother, their three college-age sons, and the boys’ friend Charles Brush Jr., all of whom were skilled in acting as volunteers and operating some of the instruments.17 Campbell was proud of his sons—Wallace Jr., Douglas, and Kenneth—who had come of age atop Mount Hamilton, jackknives in their pockets and polite smiles for the important visitors. The Lick party would travel to Genoa, Italy, by steamship, then through Austria by railway, to arrive at Kiev, where Curtis would have a temporary home waiting for them.
A cable with news of the assassinations reached the steamer carrying the BAAS members. Disturbing, yes, but so far nothing but worrisome rumblings had followed. Europe was a distant world, far away from deck activities and evening dinners aboard the ship. On July 13, they sailed into port at Cape Town, South Africa, for a visit to the Cape of Good Hope. This was where their friend Sir David Gill had been Her Majesty’s astronomer for twenty-seven years. Upon his retirement in 1906, Gill had returned to London and often invited Dyson and Eddington to his home for what he called “star-streaming dinners.” When Gill passed away that January, Eddington had been asked to write his obituary for the Monthly Notices of the Royal Astronomical Society. He did so as the steamer sailed between England and Cape Town. At night, he paced the deck, searching his thoughts for the right words. In the sky overhead was the Southern Cross, with its four brilliant stars. He had missed an opportunity to see the constellation when he was in Brazil, in 1912, it being the wrong time of year. Now, as he worked on Gill’s obituary, Eddington was more appreciative of those southern skies and “the finest stretch of the Milky Way” that flowed over his head. With the archduke’s murder now days old, the steamer sailed around the Cape of Good Hope and headed for Perth, Australia.
On July 17, the Royal Observatory team left London. Dyson had put Davidson, the man he often referred to as “the finest instrument in the Royal Observatory,” in charge of this expedition to Minsk. The soft-spoken Davidson, known for his dry sense of humor, had become indispensable for his knowledge of the instruments. This was his fourth eclipse expedition, the previous one being with Eddington to Brazil, where they had ridden a mule in the moonlight once the rain had stopped. Accompanying him was Harold Spencer Jones, who had become chief assistant at Greenwich a year earlier when Eddington vacated that position to accept the Plumian Chair at Cambridge. Also along as a volunteer was a colorful British solicitor and amateur astronomer named Patrick Hepburn. Davidson was still not interested in Einstein’s general theory at this stage.
The three Englishmen left London aboard the small Russian steamer Imperator Nikolai II, which serviced ports in Russia, Germany, and England. The ship saved time by taking the 60-mile-long Kiel Canal that cut across northern Germany to the Baltic Sea, saving some 250 nautical miles of travel. They crossed the Baltic and sailed into the Gulf of Finland to land at Saint Petersburg on July 22. They had planned a quick visit to Moscow before arriving in Minsk. But the decision turned out to be an upsetting, even dangerous one. Below their hotel room windows, on the city streets, angry crowds were forming in demonstrations and demanding war. Uneasy, the Englishmen left Moscow the next morning.
The other two British expeditions also set sail. The Solar Physics Observatory in Cambridge left in mid-July to travel to Theodosia, on the Black Sea. Headed by Hugh Frank Newall, this group would meet up with Freundlich and Perrine in Odessa, Russia, and they would sail together from there. The team from the Imperial College left later than all the others, on July 25. With Alfred Fowler at the helm, they were headed to Kiev, where they would set up camp in the university’s botanical gardens.
Perrine and Mulvey had sailed through the Straits of Gibraltar and on into the Mediterranean when they received news of the archduke’s murder. Just south of Toulon, France, they watched French warships going through military maneuvers. After reaching Italy, Perrine decided that the ships had been too slow. In Genoa, they let the instruments sail on without them, keeping only the optical components. To reach Odessa, they would have to skirt Serbia, where the royal couple had been murdered. They boarded a train and rode north to Vienna, which they reached on July 15, and continued on toward Russia. This was almost a month to the day since they had left Argentina.
Police on horseback now patrolled the streets of Vienna, and the railway was heavily guarded by troops. Towns and cities in Poland swept past their windows as the train sped down to the border of Russia. Here, their passports and all reading materials were carefully checked by customs officials. After eating at the station, they changed trains for the journey to Odessa and slept soundly in comfortable berths. As they entered the eastern part of the Russian steppe, they watched from their windows Cossacks putting their horses through drills. In Odessa, they visited the observatory, met with the Argentine general consul, and waited for the Germans and the Englishmen to arrive. From there, they would travel on to Theodosia as a group.
Father Cortie and his fellow Jesuit priest, with a shorter distance now to travel, having been banned from Russia, left Hull, England, on a steamer bound for Gothenburg, Sweden. The men then went by railway to Stockholm and on to Hernösand the next day by boat. The dozen or so expeditions from other observatories in Europe were also on the move or had already arrived at their destinations. With the expeditions focusing on the upcoming eclipse, the world continued to explode around them. Einstein’s world was also exploding.
Since the spring of 1914, Einstein had been settled in Berlin with his family. He was still working on his general theory and other papers. Now, he no longer had to mail love letters to his cousin-turned-girlfriend. He could deliver them in person if he wished, since Elsa Einstein Löwenthal also lived in Berlin. Mileva was not happy with the move from Zurich or with her life in general. By mid-July, with the anger and frustration now boiling between her and Albert, she moved with their sons to the home of Fritz Haber, a family friend and chemist at the institute who had been instrumental in bringing Einstein to Berlin.
Albert took this opportunity to draft a stunning document to his wife and the mother of his two sons. It was so devoid of warmth or kindness that calculations on a blackboard would have seemed more affectionate. The document spelled out the conditions under which he would remain living in the same house with Mileva as her husband. Given that it was also written by the same genius whose other papers would change the face of physics, it bears reprinting here:
CONDITIONS:
A. You will make sure:
1. that my clothes and laundry are kept in good order;
2. that I will receive my three meals regularly in my room;
3. that my bedroom and study are kept neat, and especially that my desk is left for my use only.
B. You will renounce all personal relations with me so insofar as they are not completely necessary for social reasons. Specifically, You will forego:
1. my sitting at home with you;
2. my going out or traveling with you.
C. You will obey the following points in your relations with me:
1. you will not expect any intimacy from me, nor will you reproach me in any way;
2. you will stop talking to me if I request it;
3. you will leave my bedroom or study immediately without protest if I request it.
D. You will undertake not to belittle me in front of our children, either through words or behavior. 18
This ultimatum may have been Albert Einstein’s most unique thought experiment yet. Even after Mileva agreed to his terms, he wanted reassurance that she fully understood what they meant. While he could not be her friend, as he wrote back to her, he could behave as her business partner. They could live in the same house so that he would not lose his sons. “In return, I assure you of proper comportment on my part, such as I would exercise to any woman as a stranger.” With this letter, the woman he had loved above his family’s fervent disapproval, his “Dollie,” his “little witch,” finally understood that it was over. By this time, Mileva was walking with difficulty and was battling bouts of depression. It would be impossible to live under the same roof with her husband and endure such unkind terms. She would take the children and leave Berlin.
Albert now had to support another household. He drafted a second document that would give Mileva and the boys a bit less than half his salary. With family friend Michele Besso escorting her, Mileva and her sons left on a train for Zurich. Albert had accompanied his family to the railway station. Once the train pulled away, according to friends, he cried all the way home and all afternoon and evening. Perhaps it was not just for the loss of his boys, but also for the loss of what had been so passionate and overpowering a love story just a dozen years earlier.
The same afternoon that Mileva’s train pulled out of Berlin, a love letter, written by a British naval officer to his wife, would suggest an opposite kind of matrimony. “My darling one and beautiful,” Winston Churchill wrote to Clementine, who was expecting their second daughter that autumn. “Everything tends toward catastrophe and collapse.” He was speaking of world affairs and not their close and loving marriage. Churchill already knew war firsthand, as a soldier and correspondent. Yet the devoted husband welcomed World War I with open arms, even relished it. He was now ready to prove his worth as a military strategist. On the other hand, Einstein, the failed husband whose letter to his own wife seemed to be one of hatred, not love, was against all wars, a pacifist.
Worlds within and without were now colliding, and conditions were being laid down by governments, not just husbands. On July 28, 1914, the day before Mileva’s train left Berlin, Austria-Hungary had declared war on the Kingdom of Serbia. Countries in Europe would soon begin mobilizing. That wrong turn by the chauffeur was starting to take its toll. As Churchill waited to see if he would get his fight, Einstein was now poised to get his own wish: “Nothing more can be done by the theorists. In this matter it is only you, the astronomers…” His faith was riding on three men: Erwin Freundlich, Charles Perrine, and William Campbell. These stargazers were also mobilizing. As if they were magi, the three teams had traveled far. They were now in Russia, setting up their wares and waiting for one bright star to give them a message.