The Planet Mars:
A History of Observation and Discovery

William Sheehan

Chapter 6
Confirmations and Controversies

The next opposition took place in November 1879. Schiaparelli found the winter air at Milan unusually calm and transparent, yielding excellent images. Moreover, he had begun to experiment with new techniques for observation. He illuminated the telescope field to suppress the effects of contrast between the bright planet and the surrounding sky, and by keeping his eye at the eyepiece no longer than necessary to obtain the best views, he was able to avoid eye fatigue and thus work effectively for several consecutive hours when the atmospheric conditions were very good. He also used a yellow filter in front of the eyepiece to improve the contrast of the shadings against the yellowish disk.1

Using these precautions Schiaparelli was able to add significant results to the work he had begun at the previous opposition. He obtained micrometric measures of 114 points on the surface---including, on November 10, 1879, a small whitish patch (half a second of arc across) in the Tharsis region. He named it Nix Olympica (the Snows of Olympus) and noted that frequently it seemed to be the site of whitish veils.2 Also important was his observation that some of the dark areas had changed since 1877. In particular, Syrtis Major seemed to have invaded some of the neighboring bright area of Libya. This seemed consistent with Schiaparelli's "maritime" view of the planet, according to which the dark areas were shallow seas that at times flooded parts of the adjoining lands. As for the canals (as we shall henceforth call them, without apology or quotation marks), they were represented as finer and more regular than they had appeared at first (fig. 9). Moreover, one of them showed up double---the Nilus, between Lunae Lacus and Ceraunius. "To see it as two tracks regular, uniform in appearance, and exactly parallel, came as a great shock," Schiaparelli wrote.3 This was the first instance of the bizarre process he called "gemination," of which I shall have more to say presently.

Schiaparelli was nothing if not sure of his results, and he wrote of the canals to Nathaniel Green: "It is [as] impossible to doubt their existence as that of the Rhine on the surface of the Earth.4 Green was also active, observing the 1879 opposition at St. John's Wood, London, though complaining that "the definition afforded by the St. John's Wood atmosphere has barely sufficed to identify the details of the Madeira observations." He was at best lukewarm to the results from Milan, declaring that "faint and diffused tones may be seen in places where Professor Schiaparelli states that new canals appeared during this opposition."5

Having embraced (with some changes) Proctor's nomenclature for his own 1877 map, Green was also unenthusiastic about the new Schiaparellian names. "I desire to make an earnest protest against change," he pleaded. "The present names have been in use for many years, they are to be found freely in the publications of the Royal and other astronomical societies, and have been accepted by a large number of workers at the Martial surface. . . . The names Kaiser Sea, De La Rue Ocean, or Dawes' forked bay, are as familiar as household words to those who employ either pen or pencil in this cause, and an affection for old names is at least an excusable weakness."6

The striking contrast between the two rival maps of 1877 did not pass unnoticed. Rev. T. W. Webb later pointed out the difference between them:
There is a general want of resemblance that is not easily explained, till, on careful comparison, we find that much may be due to the different mode of viewing the same objects, to the different training of the observers, and to the different principles on which the delineation was undertaken. Green, an accomplished master of form and color, has given a portraiture, the resemblance of which as a whole, commends itself to every eye familiar with the original. The Italian professor, on the other hand, inconvenienced by colour-blindness, but of micrometric vision, commenced by actual measurement of sixty-two fundamental points, and carrying on his work with most commendable pertinacity, has plotted a sharply-outlined chart, which, whatever may be its fidelity, no one would at first imagine to be intended as a representation of Mars. His style is as unpleasantly conventional as that of Green indicates the pencil of the artist; the one has produced a picture, the other a plan.7
Green had allowed that some of the canals might be the boundaries of faint tones of shade, but he protested that Schiaparelli had not drawn accurately what he had seen. Instead, he had "turned soft and indefinite pieces of shading into clear, sharp lines."8 Ironically, Schiaparelli himself, who admitted that his 1877 map was "purely schematic," tried in his 1879 map to adopt a different style, "to better approach the true forms one actually sees on the planet, by representing with lines those features which have that appearance in the telescope and with different shades those which exhibit delicate gradations of tint." The result, he hoped, would be "more pleasing to the eye, and more agreeable to the descriptions, than the scheme of pure lines provided with the preceding memoir."9 This attempt availed little, however, for his representations of the planet in 1882, 1884, 1886, 1888, and 1890 went from strange to bizarre.

At the opposition of 1881, when the apparent diameter of Mars attained only 16" of arc (compared with 25" in 1877 and 20" in 1879), Schiaparelli obtained excellent views of areas of the northern hemisphere that had been presented obliquely at the previous oppositions. Thus, he wrote, "the vast expanses called Oceanus and the Sinus Alcinous, which in 1879 had appeared diffuse and indefinite, seemed to belong to the areas called seas, and were resolved into complex tangles of pure lines."10 Moreover, the geminations were now widespread; though Schiaparelli recorded only a few in December, they had become alarmingly profuse a month later:
Great was my astonishment on January 19, when, on examining the Jamuna . . . I saw instead of its usual appearance two straight and equal parallel lines running between the Niliacus Lacus and Aurorae Sinus. At first I believed this to be the deception of a tired eye, or perhaps the effect of some kind of strabismus, but I soon convinced myself that the phenomenon was real. From the night of January 19, I passed from surprise to surprise. On the 21st, I discovered the duplication of the Orontes, the Euphrates, the Phison, and the Ganges.11
In one month, from January 19 to February 19, 1882, Schiaparelli recorded the gemination of no less than twenty canals. Since most of the doublings had occurred some two months after the Martian vernal equinox, he speculated that they might be a seasonal phenomenon of some sort, although he freely admitted that the explanation "strained the imagination." Nevertheless, whatever their interpretation might be, he was supremely confident that he had seen them. "I have taken all possible precautions to avoid all chance of illusion," he wrote. "I am absolutely certain of what I have observed."12

Despite the initial wave of skepticism, the canals, by the mid-1880s, were slowly beginning to gain ground among observers of Mars. Otto von Struve, Wilhelm's son, who had supervised Schiaparelli's training at Pulkova, recorded his own faith without reserve: "I am sorry to say that I have never been able to see the canals, but knowing M. Schiaparelli's excellence as an observer, I cannot doubt that they are there."13 For many observers the challenge of seeing the canals was irresistible; to fail to do so was to admit observational obtuseness. Under the circumstances, it is hardly surprising that more and more observers saw---or thought they saw---the canals, the whole process bearing a distinct analogy to the story of the emperor's new clothes.

But such an analogy is not quite precise. The Martian "deserts" were not altogether bare. There was undoubtedly something in the regions where Schiaparelli drew his network. And even Schiaparelli himself had described a gradual process of recognition:
In most cases the presence of a canal is first detected in a very vague and indeterminate manner, as a light shading which extends over the surface. This state of affairs is hard to describe exactly, because we are concerned with the limit between visibility and invisibility. Sometimes it seems that the shadings are mere reinforcements of the reddish color which dominates the continents---reinforcements which are at first of low intensity. . . . At other times, the appearance may be more that of a grey, shaded band. . . . It was in one or the other of these indeterminate forms that, in 1877, I began to recognize the existence of the Phison (October 4), Ambrosia (September 22), Cyclops (September 15), Enostos (October 20) and many more.14
William F. Denning, in 1886, found with his 10-inch (25-cm) reflector that "the more complex and more delicate details of the planet appear, under the most favorable conditions, as linear shadings, which are extremely feeble, with evident gradations in tone and with irregularities which produce breaks or condensations."15 Richard Proctor wrote that "it would be useful if the appearances shown by Schiaparelli could be seen and drawn by observers with real artistic skill. No one who has ever seen Mars through a good telescope will accept the hard and unnatural configurations depicted by Schiaparelli."16 To which Camille Flammarion added:
The pencil cannot fix features which are scarcely glimpsed. But what else can one do? One can at least distinguish certain shadings, even if it is impossible to be sure of their outlines; and extra detail appears only in rare and fugitive moments of perfect transparency. Illusion or reality? It seems that such telescopic views depend only upon thought. We indicate the features with the pencil, and those which are fugitive, uncertain and perhaps atmospheric take on the same significance as those which are incontestable and permanent.17
Among the most widely publicized sightings of the canals were those made by the French observers Henri Perrotin and Louis Thollon, who used the 15-inch (38-cm) refractor at Nice in 1886. Mars was not then in an advantageous position, since even at opposition, on March 6, its apparent diameter never exceeded 14" of arc. Despite their best efforts, the two Frenchmen were long frustrated, but their persistence eventually paid off. Perrotin wrote:
Our first attempts to see the canals were not encouraging, and after several days of fruitless searching, explicable partly by the bad quality of the images and partly because of the actual difficulty of an investigation of this kind, and after once having given up and subsequently returned to the investigation, we were about to abandon the attempt indefinitely when, on April 15, I managed to distinguish one of the canals. . . . Thollon saw it similarly soon afterward. By the end of that night, under good conditions, we had been able to recognize successively several canals presenting, in nearly all respects, almost the character attributed to them by the Director of the Milan Observatory.18
Those who seek often do find. François Terby, at his private observatory at Louvain, Belgium, did as so many others did and took the Milan astronomer's latest map along with him to the telescope in order to facilitate identification of the canals: "We took inspiration from the principle announced by some great observers: `Often,' they say, `one can see well what one especially seeks.' . . . We have sought the canals of Mars in the regions where we knew that M. Schiaparelli had proved [sic] them to exist . . . and, map in hand, we have patiently and obstinately pursued these very difficult details. It is to this method . . . we owe our partial success."19

At this point I cannot resist mentioning some comments by Sir Ernst Gombrich, the noted art critic, about his rather similar experience of straining to interpret garbled radio transmissions during World War II:
I was employed for six years by the British Broadcasting Corporation in their "Monitoring Service," or listening post, where we kept constant watch on radio transmissions from friend and foe. It was in this context that the importance of guided projection in our understanding of symbolic material was brought home to me. Some of the transmissions which interested us most were barely audible, and it became quite an art, or even a sport, to interpret the few whiffs of speech sound that were all we really had on the wax cylinders on which these broadcasts had been recorded. It was then we learned to what extent our knowledge and expectations influence our hearing. You had to know what might be said in order to hear what was said. More exactly, you tried from your knowledge of possibilities certain word combinations and tried projecting them into noises heard. The problem was a twofold one---to think of possibilities and to retain one's critical faculty. . . . For this was the most striking experience of all: once your expectation was firmly set and your conviction settled, you ceased to be aware of your own activity, the noises appeared to fall into place and be transformed into the expected words. So strong was this effect of suggestion that we made it a practice never to tell a colleague our own interpretation if we wanted him to test it. Expectation created illusion.20
So it was with Mars. Schiaparelli had taught observers how to see the planet, and eventually it was impossible to see it any other way. Expectation created illusion.

Perrotin sketched more canals in 1888, now having the advantage of a new telescope, the 30-inch (76-cm) refractor of the Nice Observatory. He also reported that since 1886, Libya, an area about equal in size to France, had been completely inundated by the neighboring sea.21 Schiaparelli, as we have seen, had reported a partial inundation of the region between 1877 and 1879, and now commented enthusiastically on Perrotin's results: "The planet is not a desert of arid rocks. It lives; the development of its life is revealed by a whole system of very complicated transformations, of which some cover areas extreme enough to be visible to the inhabitants of the Earth."22

Nevertheless, Perrotin's observations were soon challenged by astronomers using another new telescope even more powerful than the one at Nice---the recently unveiled 36-inch (91-cm) Clark refractor of the Lick Observatory on Mount Hamilton (elevation 4,200 ft, or 1,280 m) in the Coast Range of California.

Though the telescope had been used in some preliminary scouting as early as January 1888, when James Keeler had discovered a new and narrow division in the outer ring of Saturn,23 the Lick Observatory's official opening was delayed until June 1888. Systematic observations of Mars were not made until July, when the planet was some three months past an only average opposition and the apparent diameter of its disk was only 9" of arc. Moreover, the planet lay far to the south, never rising more than 30° above the horizon (compared with Saturn, which had been near the zenith), and so was unable to tolerate high magnification. Under the circumstances, nothing sensational could be expected, although the director of the observatory, Asaph Hall's former colleague Edward S. Holden, announced that he, Keeler, and John M. Schaeberle had glimpsed a few of the canals. Holden also declared that "the submerged `continent' had reappeared . . . and was seen by us here essentially as it has always appeared since 1877. It was most unfortunate that the Lick telescope could not be used for this purpose until so late a date; but it has shown its great power in such work . . . and has conclusively proved that whatever may have been the condition of the `continent' previous to July it was certainly in its normal condition from that time onward."24

This was far from the last word. Despite the great power of the Lick astronomers' telescope, their observations proved to be no less subject than others to the always distracting "personal equation." The representations of Holden and Keeler differed markedly not only from those of Schiaparelli and Perrotin but also from one another, leading Flammarion to write in near despair: "Can one really suppose that it is even the same face of the planet that is being depicted here? . . . What different aspects!"25

Schiaparelli used a new telescope in 1886 and 1888---the 19-inch (49-cm) Merz-Repsold refractor. There is an interesting story concerning this telescope. Following his 1877 observations of Mars, Schiaparelli had been invited to give a lecture to the Academy of the Lynx-eyed in Rome. The talk was well attended, and he was asked to present the lecture again a few days later to the king and queen of Italy at the Quirinal Palace. This time he hinted that with a telescope as large as the great refractor at the U.S. Naval Observatory in Washington, D.C., then the largest in the world, he would very likely be able to find out even more about Mars, "a world little different from our own." He described his address as a "very exciting phantasmagory," and later told Otto Struve that "by employing a little the Flammarionesque style, I managed the affair rather well" (the reference being, of course, to the French astronomer who was well known for his passionate advocacy of the idea of extraterrestrial life).26 The king and queen were impressed, and when Schiaparelli's request for a larger telescope came before the Chamber of Deputies, it was overwhelmingly approved.

Optically, the 19-inch refractor was not quite of the same high standard as the 8.6-inch (22-cm) Merz, and it suffered from a considerable blue spectrum; nevertheless, Schiaparelli used it almost exclusively in all his observations from May 1886 onward. In 1886 he had failed to see any geminations, but in 1888 they reappeared once again, and the results he got with the large refractor surpassed his expectations. "I believe that I saw the planet well enough on 9, 25 and 27 May," he told Terby,
and I began to be almost satisfied, having confirmed at least three or four geminations. But I had a happy surprise on 2 and 4 June; and only then did I have any idea of the power of a 19-inch aperture for Mars! I then saw that the memorable days of 1879--80 and 1882 had come back for the first time, and that I could again see those prodigious images presented in the telescope field as an engraving on steel; again there was all the magic of the details, and my only regret was to have the disk reduced to 12" in diameter. Not only could I confirm the gemination of the Nepenthes (quantum mutatus ab illa!) and the reappearance of the Triton of 1877, but I could again see Lacus Moeris, reduced to a very small point, but sometimes perfectly visible and scarcely separated from the Syrtis Major.27
His views of the Boreo-syrtis and neighboring regions were not as clear, however: "What strange confusion! What can all this mean? Evidently the planet has some fixed geographical details, similar to those of the Earth. . . . Comes a certain moment, all this disappears to be replaced by grotesque polygonations and geminations which, evidently, seem to attach themselves to represent apparently the previous state, but it is a gross mask, and I say almost ridiculous."28

In 1890, Mars was considerably nearer to the Earth than it had been in 1888, but it was much farther south, making observations from Northern Hemisphere observatories difficult. Schiaparelli wrote to Terby that he had discovered a new set of canals around Solis Lacus and that Solis Lacus itself had been "unable to escape the principle of doubling which tyrannizes the entire planet: it is cut crosswise by a yellow band dividing into two unequal parts."29

At the Lick Observatory, the results with the largest telescope in the world were no more satisfactory than they had been in 1888. Holden blamed the unusually severe winter weather, which had lasted late into the spring, so that the fine seeing usually found on Mount Hamilton during the summer did not commence until late July or August, by which time Mars was receding from the Earth and too low in the west to be well observed. Nevertheless, he took evident satisfaction in announcing that "the positions of most of Professor Schiaparelli's canals have been verified by some one of us." The endorsement was not quite as resounding as it sounded, however. Only Schaeberle had seen the canals as Schiaparelli did---as narrow lines a second of arc or so in width and in a few cases, at least, double. Keeler and Holden saw only "dark, broad, somewhat diffused bands"; and Holden wondered, as Flammarion had in 1888, "why two observers should agree in their own observations, and should disagree with a third and with the discoverer of the phenomena."30

The most important observations of the season were of bright projections into the darkness beyond the terminator line. A visitor on one of the observatory's public nights had first called the attention of Holden, Schaeberle, and Keeler to one of these projections on July 5. Keeler's drawing the next night showed two projections (fig. 10), which presented "much the same appearance as the summits of lunar mountains and craters when first visible outside the terminator of the moon."31 This plausible explanation was ignored by the press, which made something far more sensational out of them: they were nothing less than signal flashes from the Martians! Inspired by such reports, someone who was looking---perhaps too obsessively---at a canal-filled map of the planet later thought he was able to discern the Hebrew letters making up the word Shajdai, the Hebrew name for the Almighty. "This observer was not a devout believer. He was a frank agnostic, and his observation was, therefore, unbiased by any religious zeal," reported the San Francisco Chronicle:
There is a wide field for thought and speculation in this appearance of the name of God standing out unmistakably on the surface of a sister planet. A study of the accompanying illustrations will make it plain how clearly the word stands out. There can be no doubt of the observer's accuracy. The first letter (sheen) is not as sharply defined as are the two others, but washings by the [Martian] ocean have undoubtedly taken place, as is proved by a glance at the original maps, where partly submerged portions of the orange-hued land are indicated. True, the magnitude of the work of cutting the canals into the shape of the name of God is at first thought appalling, but there are terrestrial works which to us to-day seem no less impossible. Besides, it is known that the difference in gravitation between Mars and the earth would make it easily possible to do far more work with far less energy on Mars than on the earth.32
With reports of Martian signal lights and strange configurations in the Martian deserts all the rage, a French widow, Clara Goguet Guzman, bequeathed 100,000 francs for a prize, named in honor of her son, Pierre Guzman, to be awarded to "the person of whatever nation who will find the means within the next ten years of communicating with a star (planet or otherwise) and of receiving a response."33 Mars, needless to say, seemed to be the most promising celestial object with which to communicate, and farfetched schemes were promoted by the score over the next few years as practical means of interplanetary communication.34 One idea was to signal Mars using large letters in the Sahara Desert, inspiring the American astronomer Edward Emerson Barnard to write a fictional account in which Earthlings finally succeeded in sending the Martians the message "Why do you send us signals?" only to receive back the reply, "We do not speak to you at all, we are signaling Saturn."35

The next opposition, in August 1892, was among the most eagerly awaited in the history of Martian studies. At the height of the Mars furor, the planet approached within 35 million miles (56 million km) for the first time since 1877. In that memorable month, Camille Flammarion put the finishing touches to the first volume of his classic La Planète Mars, an ambitious compilation and commentary on nearly every study of the planet that had been made up to that time, which remains a mine of information to this day. Flammarion's name has already appeared frequently in these pages; by 1877 he had long been one of the leading students of the red planet (fig. 11).

Flammarion was born at Montigny-le-Roi in the department of Haute Marne in 1842. His interest in astronomy was aroused at the early age of five, when he witnessed an annular eclipse of the Sun. At first he seemed destined for the priesthood, but by the time he entered the ecclesiastical seminary of the Cathedral of Langres at age eleven, his passion for astronomical observation was already well developed. A pair of opera glasses had shown him "mountains in the moon, as on the earth! And seas! And countries! Perchance also inhabitants!"---as he later put it in his rhapsodic style.36 Henceforth it was clear that if he consecrated himself to any priesthood, it would be a scientific one.

At fourteen he moved to Paris, and there he began writing a book on the origin of the world: Cosmogonie universelle. The manuscript was not published at the time, but it came to the attention of U. J. J. Leverrier, the brilliant but irascible director of the Paris Observatory. Leverrier hired Flammarion to work at the observatory as a computer, a job that was not particularly congenial to the romantic young man. At nineteen, Flammarion wrote another book, La Pluralité des mondes habités, in which he passionately argued for the existence of extraterrestrial life; it was published in 1862 and immediately became a sensation. This displeased Leverrier, who summoned Flammarion into his office to dismiss him. "I see, Monsieur," he said sternly, "you do not have to remain here. No, it is very simple. You can retire." Flammarion went from the Paris Observatory to the Bureau des Longitudes, but in 1873 Leverrier recalled him, gave him charge of one of the telescopes, and set him to work measuring double stars. In the meantime, however, Flammarion had continued his writing, and his books appeared in quick succession: Les mondes imaginaires et les mondes réels and Marveilles célestes in 1865, Études et lectures sur l'astronomie in 1867, Voyages en Ballon in 1868, L'atmosphere in 1872, Lumen in 1873, and Le terres du ciel in 1877. His most successful work, Astronomie populaire, was published by his brother Ernest in 1879, and eventually sold 130,000 copies.

In 1882, one of Flammarion's many admirers, a Monsieur Méret of Bordeaux, offered him his chateau---complete with stables, servants' quarters, and parklike setting---at Juvisy-sur-Orge, located about 30 kilometers from Paris by rail. In earlier days this structure had served as a resting place for the kings of France on their journeys between Paris and Fountainbleau, and in one of its rooms Napoleon Bonaparte had learned, on March 30, 1814, of the capitulation of Paris and the downfall of his empire. With his own funds Flammarion proceeded to build an observatory---dedicated, like a temple, to the planet Mars---in which he hoped to realize his dream of discovering extraterrestrial life. He erected a 9-inch (24-cm) Bardou refractor in a dome on the roof of the chateau, and spent May to November of each year at Juvisy; the rest of the year he and his wife, Sylvie, continued to live in their fifth-floor apartment in the Rue Cassini, near the Paris Observatory. In 1887, Flammarion founded the Société Astronomique de France, and served as editor of its monthly publication, L'Astronomie.

Sylvie Flammarion furnished some personal details about her remarkable husband to a San Francisco Call reporter named Robert Sherard, who visited Paris in May 1893:
Flam is an extremely methodical man. He gets up regularly every morning at 7 o'clock and spends quite a long time over his toilet. Savants as a rule are a very untidy set, and Flam is an exception to the rule. . . . At a quarter to 8 every morning he has his breakfast, with which he always takes two eggs. From 8 to 12 he works. At noon he has his déjeuner, over which he spends a long time. He is a very slow eater. From 1 to 2 he receives visitors, and as he is constantly being consulted on all sorts of questions by Parisian reporters, he is usually kept very busy during this hour. From 2 to 3 he dictates letters to me. . . . At 3 o'clock he goes out and attends to his business as editor of the monthly magazine which he founded and to his duties as a member of various societies. He is back home again at 7:30, when he has dinner and spends the rest of the day in reading. He is a great reader, and tries to keep himself au courant with all that is said on the important topics of the day. At 10 o'clock he goes to bed, for he is a great sleeper.37
Though a skillful observer in his own right, Flammarion was obviously far too busy to devote much time to direct telescopic work, and he turned over most of the systematic research at Juvisy to his assistants. In 1892 his staff included Messieurs Guiot, Quénnisset, Schmoll, and Mabir; the next year he was joined by a particularly notable figure, the young E. M. Antoniadi.

Flammarion, in La Planète Mars, accepted the maritime view of Mars---that the dark areas were seas and the light areas continents. The existence of seas was shown, he said, by the frequent changes in tone in the dark patches, because such widespread and rapid changes indicated a liquid element rather than solid ground. Less of the surface was covered with water than on Earth, and the Martian seas were clearly "of Mediterranean shallowness." Sometimes they flooded the intermediate regions; at other times they retreated, leaving bare islands. As for the reddish color of the continents, "If the color is of visible ground---that is to say, of the surface," he speculated, " . . . we can assume that the surfaces are sterile and sandy. [But] to us, it seems impossible to condemn a world to a fate of this kind, above all a world in which all the elements of life seem to come together as they do on Mars."38 Instead, he thought, the reddish color must be from vegetation:
Why, we may ask, is not the Martian vegetation green? Why should it be?---is the reply. From this point of view, there is no reason to regard the Earth as typical in the universe. Moreover, the terrestrial vegetation can itself be reddish, and has been for the majority of the continents; the first terrestrial plants were lycopods, whose color is a "Martian" reddish yellow. The green substance which gives our vegetation its color---chlorophyll---is made up of two elements; one green, the other yellow. These two elements can be separated by chemical processes. It is therefore perfectly scientific to admit that under conditions different from those on Earth, the yellow chlorophyll can exist alone, or be dominant.39
Flammarion maintained that Mars was at a later stage of evolution than Earth, which explained the relative scarcity of water on its surface and the comparative smoothness of its continents.40 Mountains, he said, are rare, though the terminator projections proved that some peaks exist.

At last he came to the problem of the canals. This, he acknowledged, was "the most delicate part" of his book.41 Though personally he had succeeded in seeing only the broadest of the canals (Nilosyrtis, Ganges, and Indus), he accepted the existence of the Schiaparellian network. But explanation was not so easy. There was nothing analogous to the canals on Earth. He rejected the idea of the physicist A. Fizeau that they might be open crevasses in immense ice fields, and also the view of E. Penard that they were cracks caused by the cooling of the planet; they were simply too regular to allow such explanations. "On a globe," he asked, "could Nature trace such straight lines, cutting each other in such a fashion? . . . The more we look at these drawings, the less that we can attribute them to blind chance."42 In the end, he concluded that the canals were watercourses, adding: "The actual conditions on Mars are such that it would be wrong to deny that it could be inhabited by human species whose intelligence and methods of action could be far superior to our own. Neither can we deny that they could have straightened the original rivers and built up a system of canals with the idea of producing a planet-wide circulation system."43 Such were Flammarion's views in 1892.

Flammarion was able to make out only a few of the canals at Juvisy in 1892, and another essentially negative report was given by Charles Augustus Young, a distinguished American solar astronomer, who used the 23-inch (58-cm) and 9-inch (23-cm) refractors at the Halsted Observatory in Princeton. Young was a skeptic when it came to the detailed reports of canals given by users of smaller telescopes, and he wrote pointedly: "When I have failed to see with the large instrument anything I supposed I saw with the smaller, it has turned out on examination that the larger instrument was right, and that imagination had constructed a story that was not true by building up faintly visible details and hazy suggestions furnished by the smaller lens."44

Perhaps the most famous astronomer to fail to make out any of the canals was Asaph Hall, although in his case the failure was widely and plausibly attributed to the poor atmospheric conditions that prevailed in Foggy Bottom, the unfortunate location of the U.S. Naval Observatory (the telescope was later, in 1893, moved to northwestern Washington, D.C.). Indeed, recall that R. S. Newall, lamenting the dismal results achieved with his large refractor, had commented, "Atmosphere has an immense deal to do with definition."45 This was especially true when large telescopes were concerned. As Schiaparelli had once pointed out, a star or planet that appeared well defined and quiet in a small telescope with a magnification of 50x became a distorted mass in continual turmoil in a large telescope with a magnification of 500x. Ultimately, Schiaparelli believed, the only solution would be "to put large telescopes on top of tall isolated mountains, such as Teneriffe or Etna, where much of the atmosphere lies under the feet of the observer, and the effects of its agitation can be partly eliminated."46

The first actual experiments in this direction were made by Charles Piazzi Smyth, who set up a temporary mountain observatory on the peak of Teneriffe (12,192 ft, or 3,720 m) in 1856. His reports, historian of astronomy Agnes M. Clerke later wrote, "gave countenance to the most sanguine hopes of deliverance, at suitably elevated stations, from some of the oppressive conditions of low-level star-gazing."47 The first permanent mountaintop observatory was the Lick, established in 1888, followed in 1891 by Harvard Observatory's Arequipa Station, placed at an altitude of 8,100 feet (2,470 m) in the Peruvian Andes. Arequipa was at almost twice the elevation of the Lick Observatory, and its director, William Henry Pickering, claimed that the atmospheric conditions were nearly perfect for planetary observations with the observatory's 13-inch (33-cm) refractor.

Pickering himself quickly became the most prolific---and controversial---observer of the 1892 Mars opposition, which, owing to its far southerly location, was best observed from the Southern Hemisphere. In a year when the Lick observers found it impossible to use more than 350x magnification on their 36-inch refractor because of the planet's low altitude (even so, they succeeded in making out a number of canals), Pickering used 475x and even 1,140x, and reports drawn from his enthusiastic dispatches, printed in the New York Herald, were nothing short of sensational:
September 2. Mars has two mountain ranges near the south pole. Melted snow has collected between them before flowing northward. In the equatorial mountain range, to the north of the gray regions, snow fell on the two summits on August 5 and melted again on August 7.

October 6. Professor Pickering . . . has discovered forty small lakes in Mars.48

Pickering published more authoritative reports in the journal Astronomy and Astro-Physics.49 "Many so-called canals exist upon the planet," he wrote, "substantially as drawn by Professor Schiaparelli. Some of them are only a few miles in breadth." He was unable to see even a single gemination, but he did find several "well-developed canals" in the dark areas.50 This, in his opinion, showed that the latter could not be actual oceans; their greenish tints, he suggested, "might with some show of probability be attributed to the presence . . . of organic life upon the planet."51 Instead of Flammarion's yellowish red vegetation, Pickering believed in the ordinary greenish variety. Indeed, as we have seen, the idea that the dark areas might be tracts of vegetation had been proposed by E. Liais as early as 1860.

In addition to terminator irregularities such as had been seen at Lick, Pickering made out projections at the limb. In both cases he interpreted the appearances as due to high-altitude clouds rather than mountains. He calculated their heights at around 20 miles (32 km), which made them loftier than the clouds of the Earth---a result, he noted, that was only to be expected given the planet's lesser mass and lower surface gravity.

With the exception of Pickering's results from South America, the opposition of 1892 was a disappointment. It did not lead to developments of significance comparable to those of 1877, when the canals and satellites were discovered. As Clerke summed it up: "The low altitude of the planet practically neutralised [the advantage of distance] for northern observers, and public expectation, which had been raised to the highest pitch by the announcements of sensation-mongers, was somewhat disappointed at the `meagreness' of the news authentically received from Mars."52 Yet it was undoubtedly significant that observers using the largest telescope in the world had apparently confirmed Schiaparelli's findings. Clerke, at any rate, was impressed, and concluded that "the `canals' of Mars are an actually existent and permanent phenomenon."53

© 1996 The Arizona Board of Regents

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