|The Planet Mars: A History of Observation and Discovery|
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The next opposition of Mars after 1892 occurred on October 20, 1894. At 41 million miles (65 million km), Mars was slightly farther away from the Earth than it had been in 1892. But the greater distance was more than offset by the red planet's greater altitude in northern skies. Indeed, this proved to be one of the most memorable oppositions in the history of Martian exploration---not least because of the emergence on the scene of Percival Lowell, of whom one of his biographers rightly said that "of all the men through history who have posed questions and proposed answers about Mars, [he was] the most influential and by all odds the most controversial."1 Ideas about Martian life had been floated by Schiaparelli, Flammarion, and others, but it was left to Lowell to fashion them into a coherent whole.
Percival Lowell was born in Boston on March 13, 1855, the eldest son of Augustus and Katharine Bigelow Lowell (fig. 12). There was blue blood on both sides of the family. An ancestor, Percival Lowle, had come to what later became known as Newbury, Massachusetts, in 1639. A Bristol merchant, Lowle had followed John Winthrop, the "Lodestone of America," to the Massachusetts Bay Colony at the advanced age of sixty-seven---an undertaking that attests to the almost manic energy that characterized many of his descendants as well.
In addition to their energy, the Lowells tended to exhibit talents for mathematics and literature. Percival Lowell had both in unusual degree, as well as a personal magnetism that many who knew him remarked. Thus journalist Ferris Greenslet wrote: "This reporter has met many of the so-called great men of his time, but none with a more potent personal quality than Percival Lowell. He agrees with another witness that one felt it before, or almost before, he entered the room. It was as if one had been suddenly deposited in a powerful magnetic field."2
The early Lowells, although prominent in Massachusetts affairs, were not remarkably wealthy. This changed in 1813 when Francis Cabot Lowell, Percival's great-great-uncle, decided to build a cotton mill at Waltham, Massachusetts, with spinning machinery and a practical power loom modeled on those he had recently seen in the Lancashire textile mills of England. "I well recollect," said Nathan Appleton, a leading stockholder, "the state of admiration and satisfaction with which we sat by the hour watching the beautiful movement of the new and wonderful machine, destined as it evidently was to change the character of all textile industry."3 In the office of the textile business of his paternal grandfather, John Amory Lowell, Percival Lowell would later work and amass his own fortune. On the other side of the family, his maternal grandfather was Abbott Lawrence, onetime minister to the Court of St. James's. Indeed, the Lawrences were as well-off as the Lowells, with their own textile fortunes. Both families had Massachusetts cities named for them.
Lowell was educated at various private schools in the United States and abroad, and by the age of ten was fluent in French. At eleven he composed a hundred lines of Latin hexameters on the loss of a toy boat. At about this time his father, Augustus, settled the family in the mansion he called Sevenels (so named because there were seven Lowells living there), at 70 Heath Street in Brookline, Massachusetts. Percival no doubt enjoyed rambling about the family estate, which was later affectionately described by his younger sister, Amy, the iconoclast cigar-smoking poet:
|Sevenels made a corner where two roads join. . . . I remember them as unfrequented
country roads. The place is surrounded by a wall of uncemented pudding-stone over which
predatory boys have made it impossible to grow vines. There is an entrance on each road
flanked by heavy stone posts, and just inside the wall runs a wide belt of trees, mostly
elms, but with just enough evergreens to keep the whole inviolate from the eyes of
Within this belt of trees runs a wide meadow, kept from mowing, in June a glory of daisies and buttercups nodding in the wind, a paradise to a child, as I well remember. . . . Beyond the meadow begins the grove. A little handful of land so cunningly cut by paths and with the trees so artfully disposed that one can wander happily among them and almost believe that one is walking in a real wood.
The house itself stands in the midst of lawns and grass terraces. The South Lawn, fringed by trees and bordered with hybrid rhododendrons and azaleas, drops sheerly down to a path, at one end of which is an old fashioned arbour covered with wisteria and trumpet-vines, and two flights of stone steps lead into a formal sunken garden.4
It was in the cupola of the roof at Sevenels that fifteen-year-old Percival Lowell set up his first telescope---a 2.25-inch (6-cm) refractor.
Later, at Harvard, Lowell excelled in English composition and mathematics and won the Bowdoin Prize for his essay "The Rank of England as a European Power from the Death of Elizabeth to the Death of Anne." He graduated with honors in 1876, giving, as his part in the commencement exercises, a talk on the nebular hypothesis of Laplace (drawn very heavily from the English philosopher Herbert Spencer). His cousin, the poet James Russell Lowell, referred to Percival as "the most brilliant man in Boston";5 and one of his professors, the distinguished mathematician Benjamin Peirce, invited him to stay on at Harvard to teach mathematics. Lowell declined---"because I preferred not to tie myself down," he later recalled, "not because mathematics had not appealed to me as the thing most worthy of thought in the world."6 Instead, with his cousin and freshman roommate, Harcourt Amory, he opted for a Grand Tour of Europe as far as Syria, and though he had so recently refused to tie himself down to "the thing most worthy of thought in the world," he almost managed to get himself enlisted for the front in the war between Serbia and Turkey.
On returning to the United States in 1877, the year of Schiaparelli's fateful discovery of the Martian canals, still having no impulse to a profession, Lowell went to work in his grandfather's textile business, where he remained for six years, learning the ways of business, for a time acting as treasurer---that is, as the executive head of a cotton mill---and managing trusts and electric companies. In 1883 he left the family business and set sail for the Far East, the first of three such voyages he would make over the next decade. The circumstances surrounding what must have seemed a sudden decision were in some ways similar to those that later led him to turn to Mars. Inspired by the 1882 lecture series on Japanese culture given by zoologist Edward Sylvester Morse at the Lowell Institute (founded by Percival's great-uncle, John Lowell, and run by his father, Augustus Lowell), he was seized by a sudden enthusiasm to join Morse's crusade to preserve traditional Japanese culture in the face of rapid modernization.7 In Tokyo, he rented a house, hired Japanese servants, and began to learn the language.
When he was approached to accompany a special trade mission from Korea to the United States, he hesitated, "mainly due," as his brother Abbott Lawrence Lowell later put it, "to anxiety to what his father would say."8 However, he received encouragement from another cousin, William Sturgis Bigelow, a Boston physician who shared his enthusiasm for the Orient. Bigelow wrote to Augustus Lowell that although Percival "distrusts himself too much, he has great ability, he has learned Japanese faster than I ever saw any man learn a language---and he only needs to be assured that he is doing the right thing to make a success of anything he undertakes, whether science or diplomacy."9 (In fact, Lowell's accomplishments as a linguist were somewhat exaggerated, for apparently he never did succeed in achieving either fluency or literacy in Japanese.)10 Nevertheless, the young Lowell overcame any opposition on his father's part and any doubts of his own abilities that he might have harbored, for, as Ferris Greenslet remarked, "this was the last occasion in which there is any record of such distrust."11
After the Korean mission completed its aim of establishing trade relations with the United States, Lowell returned to Seoul with the Korean delegation, and, as a diplomatic official, was given a house forming part of the Foreign Office. The situation in Seoul must have been quite appealing to someone with Lowell's poetic temperament, as his description of his house there indicates: "From the street you enter a courtyard, then another, then a garden, and so on, wall after wall, until you have left the outside world far behind and are in a labyrinth of your own."12
Lowell remained in the Far East for ten years, returning home only to see his books through the publication process: Chosön: The Land of the Morning Calm in 1886, The Soul of the Far East in 1888, and Noto in 1891.13
Despite his strong attraction to Japanese art and gardens, his romantic impulse for the Far East was soon tempered by his irritation at the inefficiency and irrationality of premodern people. His 1891 trip to the peninsula of Noto, for example, concluded with the following reflection: "From below, by the river's mouth, the roar of the surf came forebodingly up out of the ashen east; but in the west was still a glory, and as I turned to it I seemed to look down the long vista of the journey to western Noto by the sea. I thought how I had pictured it to myself before starting, and then how little the facts had fitted the fancy."14
In the last of his Far Eastern books, Occult Japan (1895), Lowell took up the subject of Shinto trances, which he had first witnessed on the summit of Mount Ontaké, and described the séances he had held in his own house ("red flame and potent spells in a dark dark room," he described them to his friend Frederic Jepson Stimson). His experiments included rather cold-blooded attempts to test the sensibility of the trance subjects by sticking pins in them. The journalist Lafcadio Hearn, who had greatly admired Lowell's earlier work and who spent most of his own adult life in Japan, characterized Occult Japan as "painfully unsympathetic, Mephistophilean in a way that chills me."15
As Lowell's infatuation with the Far East began to wane, his boyhood interest in astronomy came once more to the foreground. It was premonitory of the change in direction his career was about to take that on his last voyage to Japan, in late 1892, he carried with him a 6-inch (15-cm) Clark refractor, which he used to observe Saturn from his Tokyo residence---Mars being neglected only because it was already past opposition by that time.
Indeed, as early as 1890 he had begun to correspond about Mars with William H. Pickering. After the 1892 opposition, Pickering was dismissed from his post at Arequipa by his older brother, Edward C. Pickering, the director of the Harvard College Observatory, who disapproved of his brother's rather sensationalistic results about Mars (William had been sent to Arequipa primarily to obtain stellar spectra, not to observe planets) and his inability to stay within his budget. On returning to Boston, William tried to interest Edward in sending a Harvard expedition to the Arizona Territory, where he expected to find excellent seeing, in order to observe the coming opposition of Mars in October 1894. When that effort failed, he immediately began casting around for other funding sources. He had not yet succeeded in lining up any firm support when, in January 1894, he heard from Percival Lowell.
Lowell's decision to take up astronomy in earnest, though it had been long in developing, apparently came rather suddenly. As late as October 1893, as he was preparing to leave Tokyo for the last time, he wrote to artist Ralph Curtis that he was considering an Easter jaunt to Seville in the spring of 1894. He returned to Boston in December 1893 and received Camille Flammarion's La Planète Mars as a Christmas gift from his aunt, Mary Putnam, read it at lightning speed, and scrawled "Hurry" across the page.16 The Lowell family motto was Occasionem cognosce---"Seize your opportunity." Lowell realized that the scientific investigation of Mars presented such an opportunity, but the last really favorable opposition of the century was fast approaching. He would indeed need to hurry if he was to take advantage of it.
In the throes of his new enthusiasm, Lowell arranged to meet Pickering on or about January 17, 1894. The intermediary for the meeting was probably Lowell's cousin Abbott Lawrence Rotch, an amateur meteorologist who in 1885 had founded the Blue Hill Meteorological Observatory outside Boston and had just returned with Pickering from Peru, where he had set up a meteorological station at Arequipa. Within a week of the meeting, Lowell and Pickering had come to terms on an expedition of the Harvard Observatory to Arizona for the purpose of observing Mars. At first, both of the Pickering brothers seem to have assumed that Lowell intended to act primarily in the role of patron, but Lowell soon made it clear that he had no interest in merely "going along"; he fully intended to keep control of the expedition himself. The agreement with Harvard was somewhat acrimoniously dissolved, and Lowell worked out a different arrangement whereby William Pickering and Andrew Ellicott Douglass, a young graduate of Connecticut's Trinity College who had been Pickering's assistant at Arequipa, would be granted one-year leaves of absence from Harvard so that they could accompany him to Arizona, in return for which Lowell would personally pay their salaries.17 Seth Carlo Chandler, Jr., wrote to E. S. Holden at the Lick Observatory that Edward Pickering had attempted to capture the new observatory for Harvard, "but found he had caught a Tartar in Lowell who is one who can see through a millstone and not one it is safe to play as a sucker."18 Henceforth the observatory would be known eponymously as the Lowell Observatory.
With Lowell having established firm control, the expedition to Arizona now moved ahead. For telescopes, they would borrow a 12-inch (30-cm) refractor from Harvard and take along an 18-inch (46-cm) refractor recently finished by optician John Brashear in Pittsburgh. Pickering drew up designs for a lightweight dome to be made of canvas and wood. Meanwhile, the location of the observatory---in many ways the crucial factor---had yet to be chosen. Douglass was sent west in early March to scout out sites, taking along the 6-inch refractor Lowell had used in Japan. With this instrument he planned to test the seeing, using a ten-point scale developed by Pickering at Arequipa that was based on the appearance of a bright star's diffraction disk and rings.19 Douglass arrived in Tombstone by March 8 and tested the seeing there, then went on to Tucson, Tempe, and Phoenix in southern Arizona before veering north to Prescott and Ash Fork. Finally he came to Flagstaff, on the main Santa Fe Railroad line to California. The altitude at this site (7,000 ft, or 2,100 m) on the Coconino Plateau appealed to Lowell, who wrote Douglass that "other things being equal, the higher we can get the better."20 Douglass found the results good in the few observations he made in the "opening in the woods" on the mesa just west of town, but only marginally better than those he had obtained elsewhere in Arizona. Though Douglass wanted to carry out additional tests, time was running out. Thus Lowell, on April 16, decided to build the observatory in Flagstaff.
What Percival Lowell hoped to accomplish through this "speculative, highly sensational and idiosyncratic project" is well documented in an address he gave to the Boston Scientific Society on May 22, 1894, which was printed in the Boston Commonwealth.21 His main object, he stated, was to study the solar system: "This may be put popularly as an investigation into the condition of life on other worlds, including last but not least their habitability by beings like [or] unlike man. This is not the chimerical search some may suppose. On the contrary, there is strong reason to believe that we are on the eve of pretty definite discovery in the matter." To Lowell, the implications of Schiaparelli's network of canali were self-evident:
|Speculation has been singularly fruitful as to what these markings on our next to nearest neighbor in space may mean. Each astronomer holds a different pet theory on the subject, and pooh-poohs those of all the others. Nevertheless, the most self-evident explanation from the markings themselves is probably the true one; namely, that in them we are looking upon the result of the work of some sort of intelligent beings. . . . [T]he amazing blue network on Mars hints that one planet besides our own is actually inhabited now.|
With this lecture Lowell had "taken the popular side of the most popular scientific question about," as W. W. Campbell would later declare,22 and had---in rather unscientific fashion---announced his conclusions before he had even put eye to eyepiece.
Lowell documented his arrival at Flagstaff, on May 28, 1894, in a letter to his mother, to whom he wrote nearly every day: "Here on the day. Telescope ready for its Arizonian virgin view. . . . Today has been cloudy but now shows signs of a beautiful night and so, not to bed, but to post and then to gaze."23 The two telescopes, the 18-inch Brashear and the 12-inch refractor borrowed from Harvard, were mounted together inside the dome designed by Pickering (which still lacked its canvas cover). The astronomers---Lowell, Pickering, and Douglass---had taken temporary accommodations in a hotel in town, but Lowell and Pickering set up camp in the dome that night to be ready for "early rising Mars." However, they were clouded out, and rain fell through the open dome. Finally, on May 31, the sky cooperated, and they used the 12-inch refractor for their first view of the planet. The following night Lowell recorded his first impressions with the 18-inch refractor: "Southern Sea at end first and Hourglass Sea . . . about equally intense. . . . Terminator shaded, limb sharp and mist-covered forked-bay vanishes like river in desert."24 Lowell's use of the word desert is remarkable, for it contains the kernel of his later theory about the planet. Perhaps Lowell's imagination had already been captured by the lonely desert south of Flagstaff, whose appearance as seen from one of the San Francisco Range peaks he later described:
|The resemblance of its lambent saffron to the telescopic tints of the Martian globe is strikingly impressive. Far forest and still farther desert are transmuted by distance into mere washes of color, the one robin's-egg blue, the other roseate ochre, and so bathed, both, in the flood of sunshine from out of a cloudless burnished sky that their tints rival those of a fire-opal. None otherwise do the Martian colors stand out upon the disk at the far end of the journey down the telescope's tube. Even in its mottlings the one expanse recalls the other.25|
Lowell and Pickering recorded the canal Lethes on June 7, and Lowell gloated: "This is the first canal seen here this opposition, and in all likelihood the first seen anywhere." Two days later he found it "very broad and glimpsed double," but still a novice to the astronomical trade, he doubted himself: "These sudden revelation peeps may or may not be the truth." On June 19 he wrote: "With the best will in the world I can certainly see no canals."26
After only a month of observing, Lowell returned to Boston, leaving the observatory in the hands of Pickering and Douglass. In Lowell's absence, Pickering attempted to measure the polarization of light from one of the dark areas but found that the reflected light from Mars was not polarized. This meant that the area was probably not covered with water.27 Douglass, meanwhile, was verifying Pickering's 1892 observation that there were canals crisscrossing the dark areas. The evidence was clearly growing that these areas were not seas after all. But if not seas, then what?
Lowell returned to Flagstaff in early August. When the observations of Mars had begun, in June, it had been early spring in the Martian southern hemisphere; now it was getting into high summer---the soufflé-thin polar cap was melting rapidly, and Lowell noted a dark band around it, which he described as a "ring of antarctic ocean."28 Later, the antarctic sea also disappeared, while corresponding changes took place in the dark areas located in the southern hemisphere---what had at first appeared as a uniform dark belt stretching "unbroken from the Hourglass Sea [Syrtis Major] to the columns of Hercules" had begun to break up into islands and peninsulas. "It will at once be seen how this bit of evidence fits into the other," Lowell suggested. "If the polar sea were thus to descend in a vast freshet toward the equator such are the appearances the freshet might be expected to present. As the water progressed farther and farther north the regions it left behind would gradually dry up, and from having appeared greenish-blue would take on an arid reddish-yellow tint; precisely what is observed to take place."29 Regarding whether the changes in tint from blue-green to reddish yellow were due to the arrival and subsequent retreat of water itself or merely its vapor, Lowell hedged. "Either water itself or vegetation its consequence would show us the first color while deserts would show the last," he wrote. "The configuration of the seas would likewise be explicable on either hypothesis. It would merely be a question of present seas or past sea-bottoms. . . . The probability is that these areas are in part water, in part fertile land."30 Although he had arrived in Flagstaff accepting the Schiaparellian maritime theory of the dark areas on Mars, he was now embracing the Liais-Pickering vegetation theory.
The canals too, which he was now sketching prolifically and in essentially Schiaparellian form, followed the general development of the broader features of the disk. "They do not all begin to develop at the same season," he announced. "Those nearest the south pole start first. The Solis Lacus is the one to lead off the list. Then the others follow in their order north. . . . Some weeks elapse after the water has to all appearance gone down the disk before the canals appear; a delay of just about the length of time it would take vegetation to sprout."31 The dark spots at the juncture of the canals, which Pickering in 1892 had called lakes, were also seen to change, not in size but in color. They seemed to deepen in hue, and this too was suggestive:
|When we put all these facts together, the presence of the spots at the junctions of
the canals, their apparent invariability [in] size, their seasonal darkening, and last but
not least the resemblance of the great equatorial regions of Mars to the deserts of our
Earth, one solution instantly suggests itself of their character, to wit: that they are
oases in the midst of that desert.
Here then we have an end and reason for the existence of canals and the most natural one conceivable---namely that the canals are constructed for the express purpose of fertilizing the oases. . . . And just such inference of design is in keeping with the curiously systematic arrangement of the canals themselves. . . . The whole system is trigonometric to a degree.32
In short, Mars was a world well on the way to utter desiccation. It was inhabited, and its inhabitants, in order to survive, had had to built a vast system of irrigation canals to transport precious water from the melting polar caps. This, in a nutshell, was Lowell's "theory," and needless to say, it created an immediate sensation.
Despite having observed the planet through only a single opposition, Lowell, in a spurt of manic energy, blitzed the press with his sensational results. He had begun publishing a series of articles on Mars in W. W. Payne's journal Popular Astronomy even before the opposition was over, and he followed that up with a similar series in the Atlantic Monthly. In February 1895 he gave a series of well-attended lectures in Boston's Huntington Hall, then concluded, finally, in December 1895 with his first book on the red planet, entitled simply Mars, in which he described in detail his observations and conclusions therefrom. Lowell's drawings and maps were even stranger than those Schiaparelli had published. To some extent this can be attributed to the fact that Lowell, for all his undoubted and diverse talents, was, as Carl Sagan has pointed out, "unfortunately one of the worst draftsmen who ever sat down at the telescope and the kind of Mars that he drew was composed of little polygonal blocks connected by a multitude of straight lines."33 To that I would add only that Pickering and Douglass were, if anything, even more maladept draftsmen!
Lowell's theory of intelligent life on Mars unleashed a firestorm of controversy. The public was fascinated, while professional astronomers generally viewed him with suspicion; some were openly hostile. Lowell had opened his Popular Astronomy series by attributing the failure of skeptics to see the evidence to the fact that they had not observed the planet in steady enough air. He added: "No amateur need despair of getting interesting observations because of the relative smallness of his object-glass. . . . In matters of planetary detail size of aperture is not the all-essential thing. . . . A large glass in poor air will not show what a small glass will in good air."34 Undoubtedly Lowell was a fast study, but it is still remarkable that he could write this after only one month of observing Mars at Flagstaff! Later, he condemned the use of large reflecting telescopes for planetary work as well, calling them "well-nigh worthless."35 After reading such sweeping comments, James Keeler, then at the Allegheny Observatory in Pittsburgh, complained to George Ellery Hale: "I dislike his style. . . . It is dogmatic and amateurish. One would think he was the first man to use a telescope on Mars, and that he was entitled to decide offhand questions relating to the efficiency of instruments; and he draws no line between what he sees and what he infers."36 Hale and Keeler, who were the coeditors of the influential Astrophysical Journal, eventually declined to publish any of Lowell's submissions in their journal.
Lowell's Martian theory immediately made him one of the most prominent men in Boston, and he did not appear to mind the celebrity, at least judging by a vignette from about this time related by Ferris Greenslet:
|He had bought for his life en garçon a small high house on the upper side of West Cedar Street. There during the winter a young editor and publisher from New York, passing with a bag of manuscripts to his own modest establishment in the next block, used to observe him every weekday at five-thirty. His handsome head was to be seen vis-à-vis the Boston Evening Transcript beneath a life-sized plaster Venus similar to those that infest the Athenaeum. Visibility was perfect, for the shade was always raised to the very top of the window as if to admit no impediment to a message from Mars.37|
After seeing his book Mars through the press in December 1895, Lowell set sail for Europe to confer with eminent Martian observers there. In Paris, he dined with Flammarion in his apartment on the Rue Cassini, describing the occasion in a letter to his father: "There were fourteen of us, and all that could sat in chairs of the zodiac, under a ceiling of pale blue sky, appropriately dotted with fleecy clouds, and indeed most prettily painted. Flammarion is nothing if not astronomical. His whole apartment, which is itself au cinquieme, blossoms with such decoration."38 In addition to their mutual interest in Mars and extraterrestrial life, the two men shared a fascination with the occult---Lowell, as we have seen, had held séances in his house in Japan, and Flammarion sometimes invited mediums to his Paris apartment. Flammarion had from the first commended Lowell for founding "an observatory inspired, as that at Juvisy, with the dominant idea of studying the conditions of life on the surface of the planets of our system."39 He subsequently recognized the importance of Lowell's Martian observations, which were, he wrote, "of the highest interest, though certainly controversial, and they advance our knowledge of the planet, even if we do not accept them as definitive."40 He could not, however, bring himself to accept Lowell's conclusion that the dark areas were tracts of vegetation. He still regarded them as seas, although, he admitted, they were in many places probably little more than marshes.41 From Paris, Lowell traveled on to Milan, where he met the man he admired above all others and always referred to as cher maître Martien. What Schiaparelli's expectations of the American may have been are less certain, though he later confided to François Terby: "It is certain that Lowell commands superior means to any hitherto employed on Mars. If his perseverance and enthusiasm do not desert him, he will make considerable contributions to areography; on the other hand, he needs more experience, and must rein in his imagination."42
At about this time the Milan astronomer was becoming increasingly aware of problems with his eyesight; while observing Mars, he confided to Terby, he was troubled by "a diminution of the sensibility to weak illuminations; I attribute this to the observations of Mercury near the Sun carried out from 1882 to 1890."43 Moreover, the air over the growing and increasingly polluted city of Milan was no longer as tranquil as it once was. Finally, in May 1898, Schiaparelli announced his retirement from observational work:
|The time has come to let others take over the careful study of the phenomena of Mars. I will publish my observations, in the hope that time will resolve the feelings of doubt and distrust with which they are received by nearly one and all. Whoever wishes to study Mars successfully, must have a keen eye (like my left eye; my right is useless for observations), and must work in a calm atmosphere with a telescope that is able to concentrate the rays in the red part of the spectrum---the other rays must be eliminated with a colored glass. Add to this as prerequisites long practice and great prudence in the conclusions one draws from the observations.44|
But though his eyes were no longer keen enough to place him in the first rank of planetary observers---indeed, he published none of the observations he made after 1890---Schiaparelli nevertheless remained the leading authority on Mars, and his pronouncements on the subject were eagerly awaited. In 1893 he penned a widely quoted paper titled "Il Pianeta Marte," in which he suggested that the canals were in all probability natural features produced during the evolution of the planet---perhaps similar to the English Channel or the Channel of Mozambique. When he turned to a consideration of the geminations, however, he admitted that it was difficult to think of a natural explanation: "Their singular aspect, and their being drawn with absolute geometrical precision, as if they were the work of rule or compass, has led some to see in them the work of intelligent beings, inhabitants of the planet. I am very careful not to combat this supposition, which includes nothing impossible."45
By 1895, Schiaparelli was not only "careful not to combat" the supposition, he seems to have embraced it. That year he published another widely quoted paper, "La Vita sul Pianeta Marte" (The life of the planet Mars), in which he wrote that the idea that the geminations were perhaps best explained as owing to the activity of intelligent beings "ought not to be regarded as an absurdity."46 On the contrary, he said, "one cannot [otherwise] comprehend how in the same valley the moisture and vegetation sometimes make a single line, in other cases two parallel lines of unequal breadth and separated by unequal intervals, between which remains a sterile space deprived of water. Here, the intervention of intelligent thought seems well indicated."47
He proceeded to work out the details of a system of locks and dikes that would both regulate the water flow on Mars for the convenience of the inhabitants and also satisfy the observations made from Earth. A remarkable performance! Yet Schiaparelli insisted that he did not mean to be taken seriously and closed with the comment, "I leave now to any lecturer who cares to do so to continue these considerations; as for me, I am descended from a hippogriff."48 To Flammarion he sent a copy of the paper, on which he wrote at the top of the page, "Semel in anno licet insanire" (Once a year it is permissible to act like a madman).49 Once again he remained, to the exasperation of his contemporaries, impenetrable when it came to his true views about the nature of the canals.
Though he later gave Lowell's theories a sympathetic hearing, writing in 1897 that the system of canals "presents an indescribable simplicity and symmetry which cannot be the work of chance," and telling Lowell himself, "Your theory of vegetation becomes more and more probable,"50 he refused to commit himself. To inquiries about the nature of the canals, he continued to respond, "I don't know!"51 In an 1899 review of Lowell's observations, he struck an all-too-familiar note of agnosticism, writing that the nature of the canals was still "entirely obscure, despite the theories, oftentimes pretty and very ingenious, which they have occasioned."52 Twenty-two years had passed since he had discovered the remarkable network, yet it remained a source of bewilderment to him. In this respect he was far from being alone. E. M. Antoniadi, Flammarion's assistant at Juvisy, wrote of the "canal deadlock" and recalled this as a time when "everything was darkness to all."53