by Sarah Dry
It comes as no surprise, given Piazzi Smyth’s lifelong commitment to watching the skies, that he was an early advocate for what he called cloud-capturing photography, a new technology to feed his endlessly voracious visual appetite. He’d grown up learning to use whatever tool suited the task of observation before him: Watercolors, pen and ink, pencil, and paints were his early tools. As a youth in the Cape of Good Hope, he had also recognized that photography had the potential to transform scientific observation. Throughout his life, he’d experimented with it, making photographs on board ships, atop mountains, and in the gloom of Egyptian pyramid tombs, developing stereo-photography and even the photography of plaster models. In the 1870s, he designed a new camera specifically for taking photographs of clouds. It incorporated a special corrector to counteract the spherical aberration otherwise introduced by a portrait lens, enabling the full aperture of the lens to be used without distortion.42 He exhibited it at the Edinburgh Photographic Society’s 1876 Exhibition, alongside some cloud photographs, and was awarded a silver medal for it.
He then abandoned the project to undertake one last, intense piece of spectroscopic research, seeking clear rather than cloudy skies in which to probe the nature of the solar spectrum as deeply as possible. Instead of Tenerife, he traveled to the more accessible Portugal and there found that he was able to almost eliminate the so-called telluric, or earthly, lines associated with water vapor. There Piazzi Smyth was finally able to separate the true solar spectrum from both the dry atmospheric spectral lines and those corresponding to moisture in the atmosphere, the culmination of the project he’d begun atop Tenerife some twenty years earlier. As proud as he may have been of the fruits of his observational labor, Piazzi Smyth was not alone in his quest to subtract earthly from solar phenomena.43 At the 1882 meeting of the British Association for the Advancement of Science, several others claimed priority in the matter of separating the solar from the dry and wet atmospheric lines. The related question of whether the oxygen bands had their origins partly in the sun also remained unanswered well into the 1890s. In 1893, an elderly Jules Janssen decided to try to settle the matter himself. At age sixty-nine, he made his way to the top of Mont Blanc in an attempt to observe solar oxygen from there. His observations of the absence of oxygen lines in the solar spectrum as viewed from the top of the mountain were taken as evidence for the absence of oxygen on the sun. The spectroscope continued to amaze with its ability to penetrate deep into the atmospheres of distant objects.
While the scientific community continued to seek evidence for new substances in the atmospheres of the earth, the sun, the planets, and even such remote phenomena as the Zodiacal light, Piazzi Smyth himself receded ever further from public view. His last undertaking was almost entirely solitary. He had both embraced the pleasures of independence and tasted the bitterness of exclusion during his lifetime. His commitment to pyramidology had resulted in his self-imposed retreat from the Royal Society and the community of scientists it represented. His spectroscopic work continued to be of excellent quality, but his insistence on using the British inch as the unit of length had severely limited the usefulness of his maps. In the end, he found himself almost alone. He had time, the luxury of retirement. He had his instruments and a few assistants to help him. And he had the clouds. They passed by the high windows of his home in Ripon, Yorkshire. He grasped them with his camera, angling it up to exclude all but the tops of the tallest trees.
FIG. 3.11. Charles Piazzi Smyth in old age with a grand-niece. Credit: Royal Observatory Edinburgh.
FIG. 3.12. Photograph from Cloud Forms That Have Been at Clova, Ripon, taken from his library window by Charles Piazzi Smyth on June 30, 1892. Credit: Royal Society.
FIG. 3.13. “The wrecks of a summer squall,” Smyth notes on the cloud photograph taken on June 30, 1892, along with observations of barometric pressure, temperature, rain- and sunband, and wind speed. Credit: Royal Society.
He returned to cloud photography, the subject he had investigated some twenty years earlier, looking for a way to standardize the observation of the clouds just as the spectroscope had standardized the observation of light. But while his earlier project had been undertaken in the acknowledgment of a wider community of observers, this final project, undertaken in 1892 and 1893, was an impossible, almost lunatic attempt to record the face of the skies alone. He himself gently mocked his project, calling it a “labour of love and meteorologic research, in days of old age and failing faculties.” At the heart of his project was a set of photographs which, without intention or ambition to extend beyond their tiny window of the world, served as a powerful renunciation of the communal approach to knowledge. Of the hundreds of images he took, he printed 144 of the best in three massive volumes, bound in leather and prefaced with a manuscript copied out in a clear hand, detailing the nature of his project. These tomes represented the work of thousands of hours, but they were read by almost no one. Never published or widely shared, they stand as a monument to life spent in intensely personal observation.44
Piazzi Smyth’s timing was, in a certain sense, excellent. At the very moment that he was devoting himself in solitude to his “labour of love,” the scientific community had begun its own project in cloud photography. Inspired in part by Abercromby’s discovery that cloud types were universal, in 1891 the attendees of an international conference of thirty-one meteorological directors from around the world launched an international project to map the clouds. Their plan encompassed not merely a single location but, in theory (if not in practice), the entire globe. The projected International Cloud Atlas would improve upon Howard’s classification system and put flesh on Abercromby’s anecdotal assertions about the universality of clouds. Headed by a Swede, Hugo Hildebrandsson, and a Frenchman, Léon Teisserenc de Bort, the atlas had the crisp mark of imperial power on it, the confidence to mark the skies with order as the railways and telegraph wires had marked the land. The plan was explicitly both global and synchronized, aiming to promote what its authors described as “inquiries into the forms and motions of clouds by means of concerted observations at the various institutes and observatories of the globe.”45 It was, in other words, everything that Piazzi Smyth’s solitary project was not.
Clouds became, through the classificatory magic of the International Cloud Atlas, standardized objects that could be identified reliably on the basis of images that served much the same purpose as the sketches of birds in a naturalist’s guide. Clouds were, the atlas declared, universal types that could be identified at any point on the planet. To aid in such identification, the atlas made stunning use of color photographs. It proved impossible, however, to capture images of all the sixteen basic types of clouds described in the atlas this way. Certain clouds, such as the alto-stratus, the nimbus, and the stratus, were too difficult to catch. Lithographic representations of painted pictures—an older technology for representing ideal types—of these cloud types appear in the completed atlas alongside color photographs, as do black-and-white photographic images. Perfect scientific vision, these different kinds of images seem to suggest, was impossible. Instead, the act of looking was an active and dynamic process. Seeing clouds well—which included seeing them as universal types—required seeing them in different ways and from different locations. This way of looking proved resilient. The International Cloud Atlas has remained in print ever since. Photography remains the standard technology for representing the clouds and, just as important, the atlas is a compendium of global knowledge, generated by observers positioned all over the planet just as Hildebrandsson and Teisserenc de Bort had suggested back in 1896. The projected future of meteorology that they envisioned has, in many important respects, come to pass.
In another, and perhaps more important sense, meteorology has changed dramatically since then. No longer is taxonomy enough. Once a system for classification had been established—not by a solitary looker like Piazzi Smyth but by a committee representing the international communit
y—the next step was to apply it to the deeper, and much knottier, problem of explaining why the clouds appeared where they did, of explaining what drove the weather and the clouds with it. For all its confidence, the Cloud Atlas was little more than a down payment on a future piece of work whose success was far from certain.
Piazzi Smyth offered no help with that project either. His life and his considerable energies had been expended in the belief that looking was an end in itself, an activity that was both morally and scientifically productive. Looking at things that were difficult to see—the distant stars, the ever-changing spectrum, the clouds—was a way to exercise mental faculties and spiritual sense at the same time. Piazzi Smyth left to others the task of seeing through clouds to the physics of the solar system or looking at a fuzzy, shifting rainband to crack the code of the weather, or capturing clouds that shifted with dizzying rapidity. He was ready to look not for explanation but for something deeper still—the mark of the divine. “Up to this time, whatever science can or cannot say in scholastic explanation,” Piazzi Smyth reasoned, “or however far behind she may be in reducing either the minute beauties of calm summer skies or the majestic agglomerations of threatening thunder . . . to nothing but a few mechanical processes throughout their whole extent and bearing, yet the forms of beauty exhibited so frequently and prodigally before our neglectful eyes in Clouds, can only be reverentially looked upon by us.” In the final consideration, clouds were noteworthy to Piazzi Smyth not because they made elusive, difficult objects for scientific study, but because they made it easy to see God. Able to be witnessed by all of us, they were testaments to divine order, bearing the “visible impress of the greater invisible Intelligence which arranges all we see.”46 At the end of a busy and tumultuous life, Piazzi Smyth took a full measure of solace from the order he found in the wildness of the sky.
4
NUMBER OF THE MONSOON
Arriving in India in 1903 at the age of thirty-five, Gilbert Walker traveled directly to the foothills of the Himalayas. His destination was Simla, the summer capital of the British Empire in India, and the year-round location of the Meteorological Department. He was on his way to assuming the most important job he would ever hold, Director-General of Meteorological Observatories.1
He had spent most of the past decade and a half at Trinity College, Cambridge, living among other single men in rooms set off private courtyards. There, he had devoted himself to the study of mathematics. Though he was about to take over the world’s most extensive meteorological network, he knew next to nothing about the weather, still less about managing an organization that included hundreds of observatories and tens of thousands of observers. That, in a sense, was the very reason he’d be summoned to India. Things had gotten so desperate, and the problem facing those who hired him so intractable, that Walker’s ignorance and lack of experience had started to seem almost desirable. When little else had worked, perhaps it was time to try something completely new. There was one single, highly reassuring fact about Walker: He was one of the best mathematicians of his generation. That was enough reason for Walker’s predecessor, John Eliot, to stake his own reputation on the tall, thin young man who had undertaken the long journey to India.
Simla, the city where Walker was headed, was just as paradoxical as Walker’s appointment. It was a cool place in a hot land, a small city in a wildly populous nation, a remote enclave from which to rule a voluminous empire. Located just over 7,000 feet above sea level and nearly 1,000 miles from Calcutta, Simla offered relief from the stupefying heat of the plains. The city had proved its worth by providing a safe, comfortable, and healthy location from which the British could rule their largest colony during the oppressive summer months. Arrayed on a steeply terraced hillside, and governed by the rhythms of the court, the town was as much redoubt as refuge, deriving its power from its very remoteness and exclusivity. “Here,” in the words of one visual atlas of the Empire, “wars are planned, peace is made, famines fought.”2
That last, alliterative phrase was the reason Walker had been summoned.
FIG. 4.1. Simla and surrounding mountains in the Himalayas. Credit: Wellcome Collection.
FIG. 4.2. Portrait of Gilbert Walker, who arrived in India at the height of famine hoping to identify the causes of the monsoon.
That remoteness could signal power—that power could be enacted from a distance and that its effects might be amplified rather than attenuated by that distance—was a thing that the British in India already knew. What they didn’t know, and what they hoped Walker would tell them, was what powers gave rise to the monsoon deluges upon which the well-being—indeed the survival—of tens of millions of Indians and the wealth of the Empire depended.
* * *
The idea that mathematics might be able to cut to the heart of a problem was not a new one in 1903. Mathematics had long been granted a special authority among scientists, dating back at least as far as Galileo’s measurement of the acceleration of falling bodies. Used properly, numbers could reveal the laws of nature. That mathematics was essential for understanding the atmosphere of the earth had also been long understood, ever since observers had gathered quantitative measurements of temperature and pressure. In the final three decades of the nineteenth century, however, both the mathematical tools, and perhaps even more importantly, the amounts of data to which they could be applied, had increased dramatically. The automatic observatories set up by the Met Office in the wake of FitzRoy’s death—recording the traces of the weather day in and day out—were generating data from which it was hoped patterns could emerge. In addition, legions of observers were diligently recording observations by hand. These observations—many of which were made by sailors in the navies and merchant marines of the ruling nations of the globe—had grown exponentially in the decades preceding Walker’s arrival in India, for the simple reason that the management of empires depended on the management of the weather. As empires had grown to subtend ever-larger portions of the globe, so the collection of meteorological data had spread to keep pace.
Climatology was the name of the field dedicated to the collection of data about the weather. Originating in German, the term made its way into English and French usage in the first decades of the nineteenth century, rising in usage from the 1840s onward. Its rise can be traced, as so much, back to Alexander von Humboldt’s influence at the start of the century (one of the earliest uses of the word was in a French translation of Humboldt’s work).3 Humboldt’s concept of climates was related to his insight into the unity of nature. This unity, according to Humboldt, did not produce climatological uniformity. Instead, myriad physical forces combined to generate climatological difference—distinct zones, often defined vertically, in which certain conditions of temperature and precipitation persisted and where certain plants and animals thrived accordingly. If the physical forces of nature were always in flux, the wonder was that they combined in such a way as to produce stable, geographically fixed climates that could be measured, described, and in a certain sense safely stowed away. Safe, in this sense, meant reliable. Humboldt expected them to endure for a long time.
The exploratory and unity-seeking arm of climatology that claims a lineage from Humboldt must be reconciled with the part of climatology that was, as it were, born statistical. In both England and Prussia, national departments for gathering meteorological data emerged from or were closely linked to state statistical offices. There, the practical benefits of knowing the changing weather patterns—and determining some general climatological rules—were enormous. Understanding climate was of practical benefit in the same way that astronomy, botany, magnetic studies, and surveying were—they allowed state holdings to be mapped and understood in order that they could be exploited. But perhaps more than any of these allied disciplines, the collection of weather data that could be transformed into climate averages was a nation-building exercise. By gathering data on both citizens and the weather, governments hoped to cont
rol these often-unwieldy phenomena.4
Julius von Hann, director of the Central Office for Meteorology and Geomagnetism in Vienna, and Wladimir Köppen, director of the German Marine Observatory in Hamburg, were the primary inheritors of Humboldt’s confidence that the earth’s face could be measured and known. They differed from Humboldt, however, on the question of how climate should be defined. Armed with the desire, the money, and the institutional capacity, Hann and Köppen transformed Humboldt’s mantra of singular exploration into the basis for a systematic discipline. In the process, the Humboldtian emphasis on the interrelationships between living creatures and the environment in defining climate gave way to a definition of climate in terms of fixed zones, identified on the basis of averaged meteorological data. Climate, as defined by Hann and Köppen, was built on the foundations of meteorological data. It was the weather averaged.
More important than the precise definition of climate (as it turned out) was the foundation that these men established for climatology. Under the direction of Hann and Köppen, climatology was a science of rigorous measurement carried out in robust institutional settings. Hann promoted his approach through a Handbook of Climatology, published in 1883, which laid out the method by which climatology could advance, step by step, as an invading army. The natural direction for this science was cartographic, and in due course Wladimir Köppen extended climatology by introducing the graphical power of the climate map, on which averaged climatic zones were represented in visually distinctive areas. The “tropical climate” was born on Köppen’s maps, alongside the “polar climate,” the “subtropical climate,” and the “Mediterranean climate.”
