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Volume 1438

Burroughs’ Barsoom and Lowell’s Mars:
A Map for the Interpretation of Barsoomian Geography
Leathem Mehaffey
A Princess of Mars, Edgar Rice Burroughs’ first novel for publication, came out in 1911 in All-Story Magazine. His description of Mars (Barsoom) with its dead sea bottoms, canals, deserted cites and polar caps was a vivid and perfect backdrop to the dramas which unfolded there. But where did Burroughs’ ideas of Mars come from? To what extent was Burroughs influenced by Schiaparelli’s “discovery” of Martian canals and by Percival Lowell’s later descriptions of life on Mars or by his more detailed description of the Martian canals? Clearly, the influence is there, and in the essay that follows I hope to trace the extent of that influence, especially as it pertains to the potential use of Lowell’s map of Mars in interpreting Burroughs’ Barsoom.

The earliest mention of the canals of Mars and a description of what its surface might look like came when Schiaparelli published his description of Mars in 1877 (later augmented in 1879). However, while Burroughs might well have been aware of Schiaparelli’s work, several things militate against that work being the source of his inspiration. To begin with, Burroughs was only two years old when Schiaparelli published his work. Then too, Schiaparelli was very careful to state that his use of the terms “seas” (mare) and “canals” or “channels” (cannali) were not to be taken literally. He specifically cited the continuing use of the term mare to refer to “seas” on the moon when it was well known that these were arid plains. In spite of his own warnings, however, Schiaparelli was convinced that at least some of his Martian mares were indeed oceans, quite the opposite of Burroughs’ later description of the dying Barsoom with its dead sea bottoms.

Percival Lowell published his book “Mars” in 1895, when Burroughs was twenty. Although a copy of this book, or Lowell’s subsequent books (“Mars and its Canals” (1906) and “Mars as the Abode of Life” (1908)) is not present in the Burroughs library, the work was very popular at the time as evidenced by articles in the New York Times (some 35 articles on Mars and Lowell from 1895 to 1910) and the serialization of “Mars” in the Atlantic Monthly in the summer of 1895. Thus Burroughs could easily have been aware of Lowell’s ideas; but I feel that the evidence shows that he was much more than simply aware of them. In fact, he must have studied them rather closely: as we shall see, many of Lowell’s facts about Mars turn up in Burroughs’ Barsoom.

In contrast to Schiaparelli, for example, Lowell denies that the “seas” are aqueous. In Lowell’s words, “Thus we see that several independent phenomena all agree to show that the blue-green regions of Mars are not water, but, generally at least, areas of vegetation; from which it follows that Mars is very badly off for water, and that the planet is dependent on the melting of its polar snows for practically its whole supply.” This scarcity of water (and its consequential limiting of other resources is a continually recurring theme in Burroughs’ Barsoom and is used by him to justify the warlike nature of the Barsoomians.

One of the more striking “anomalies” of Burroughs’ Barsoom is that it is quite warm, enabling his characters to go about nude or nearly so. But Lowell provides the answer: “contrary to what the distance of the planet from the Sun and the thinness of its atmospheric envelope would lead us to expect, the climate of Mars appears to be astonishingly mild. Whereas calculation from distance and atmospheric density would put its average temperature below freezing, thus relegating it to perpetual ice, the planet's surface features imply that the temperature is relatively high. Observation gives every evidence that the mean temperature must actually be above that of the Earth”.

Burroughs’ Barsoom boasts of a polar sea at the South Pole, the Lost Sea of Korus into which the River Iss empties. In “Mars”, Lowell says “On July 1 our Martian polar expedition disclosed what used to be the supreme quest of earthly expeditions,--that dream of arctic explorers, an open polar sea. On that day Professor Pickering perceived, in the midst of the cap, in longitude 260 degrees and latitude 80 degrees, a sheet of water about 250 miles long by 150 broad.”

Aside from the polar sea, though, Burroughs’ Barsoom consists largely of dead sea bottoms which are arid, though covered with an ochre moss-like plant. Here’s Lowell’s description: “But as a planet grows old, its oceans, in all probability, dry up, the water retreating through cracks and caverns into its interior. Water thus disappears from its surface, to say nothing of what is being continually imprisoned by chemical combination. Signs of having thus parted with its oceans we see in the case of the Moon, whose so-called seas were probably sea bottoms. On Mars the same process is going on, but would seem not yet to have progressed so far, the seas there being midway in their career from real seas to arid depressed deserts; no longer water surfaces, they are still the lowest portions of the planet, and therefore stand to receive what scant water may yet travel over the surface. They thus become fertilized, while higher regions escape the freshet, and remain permanently barren.”

Burroughs waxes lyrical in many instances about the glories of the Barsoomian night lit by dual moons. In Princess of Mars he says: “Both of Mars' moons are vastly nearer her than is our moon to Earth; the nearer moon being but about five thousand miles distant, while the further is but little more than fourteen thousand miles away, against the nearly one-quarter million miles which separate us from our moon. The nearer moon of Mars makes a complete revolution around the planet in a little over seven and one-half hours, so that she may be seen hurtling through the sky like some huge meteor two or three times each night, revealing all her phases during each transit of the heavens… The further moon revolves about Mars in something over thirty and one-quarter hours, and with her sister satellite makes a nocturnal Martian scene one of splendid and weird grandeur.” Here’s Lowell’s description: “Deimos, at a distance of 14,600 miles from the planet's centre, makes his circuit in 30 hours and 18 minutes; Phobos, at a distance of 5,800, in 7 hours and 39 minutes. [Asaph Hall, the discoverer and namer of the moons in 1877, gave essentially the same values for orbital times, but had Diemos at a distance of 12,500 miles and Phobos at 3,760 miles.] As Mars himself rotates in 24 hours and 39 minutes, Phobos goes round the planet faster than the planet turns upon itself, and, in consequence, would appear to any observers on the planet's surface to break the otherwise universal conformity of stellar motions by rising in the west and setting in the east. Deimos, too, is just as unconventional in its way, for it remains for two days at a time above the horizon. Furthermore, with each, owing to its nearness to the planet, its distance from any place on the surface varies at different times, and with its distance varies its apparent size in a somewhat startling manner. Phobos would thus, at its closest approach to the surface of the planet, that is, when it was in the zenith, just show a disk like the Moon. Otherwise both satellites would appear as stars.” I would assume that Burroughs omitted the complications of Phobos’ (Thuria’s) retrograde motion and variation in apparent size for artistic reasons.

Burroughs’ Barsoomian measurements also reflect Lowell’s Martian ones. For his Barsoomian linear measures, Burroughs gave the value of one sofad as 11.694 inches. He gave the karad as 100 haads, and said that the karad derived from the circumference of Barsoom at the equator, that distance being 360 karads. Converting from sofads to karads (there are 10 sofads in an ad and 200 ads in a haad), the circumference of Burroughs’ Barsoom can thus be calculated to be 13,288.6 miles, giving a diameter of 4229.9 miles (circumference=pi times diameter). Lowell has the diameter as 4215 miles, a figure later changed to 4220 miles (“Mars as the Abode of Life”, 1908). Using the latter Lowell figure of 4220 miles, this multiplied by 3.14896 gives the Burroughs figure of 13,288.6 miles. Unfortunately the actual value of pi (accepted from Isaac Newton’s time) is 3.14159, not 3.14869. Such a small discrepancy might, however, easily have arisen through a simple mechanical error (after all, Burroughs didn’t have access to computers or calculators!).

Burroughs divided the Barsoomian day into ten zodes, with one zode being equal to 2.462 earth hours (“A Fighting Man of Mars”), making the day equal to 24.62 hours. This agrees quite well with the value Lowell reported in “Mars” of 24.623 hours. (24 hours, 37 minutes and 22.7 seconds; Lowell improved on the previously accepted 1666 estimate by Cassini of 24 hours and 40 minutes (24.67 hours)). In “Gods of Mars” Burroughs gives the Martian year as 687 days (he did not specify Earth or Mars days, but the implication was that the measure was Earth days); Lowell gives the Martian year as 686.98 Earth days, an essentially identical value.

Upon his first advent on Barsoom John Carter is astonished to find that he can jump to great heights due, as he puts it, to the fact that “My muscles, perfectly attuned and accustomed to the force of gravity on Earth, played the mischief with me in attempting for the first time to cope with the lesser gravitation and lower air pressure on Mars.” This fits with Lowell’s description of both the lower atmospheric pressure and lesser gravity of Mars. As to the air pressure, “Now, the pressure is certainly very slight on the surface of Mars; not probably more than, and probably less than, one seventh of an atmosphere”. Lowell also calculated the gravity of Mars to be 38% of Earth’s gravity. In “Princess”, when Tars Tarkas bears down on him, John Carter jumps “fully thirty feet into the air”. Interestingly enough, a simple calculation using Lowell’s figure here shows that John Carter would be a high-jumper on earth, too, since a thirty-foot jump on Barsoom would translate to over eleven feet on Earth. One would like to know how Burroughs came up with the thirty foot figure.

Now we come to the maps of Mars and Barsoom and the degree to which the two coincide. Lowell’s most detailed maps of Mars are found in his first book, “Mars”, in which he presents two Mercator projections:

Lowell, following the precedent set by Schiaparelli, set the prime meridian at Syrtis Major, the most distinct feature of Mars, which feature had been drawn as early as 1666 by Cassini. Note that Lowell’s maps, based on telescopic observation, show North at the bottom and East on the left. The two images can be combined and slightly rearranged to give a Mercator map extending from 45 degrees north to 70 degrees south and from 180 degrees east to 180 degrees west:
 For Burroughs’ Barsoom, except in cases where the exact coordinates of a city are given in Burroughs’ stories, I used the orthographic maps presented by David Bruce Bozarth (, which themselves are reproductions of original maps reproduced in Post’s “An Atlas of Fantasy”. Superimposing on them a global grid with 10 degree latitude and longitude lines allows a measurement of the coordinates of each city. These coordinates are then transformed into Mercator projection (Mathematica, from Wolfram Associates) and then superimposed on the Lowell map:
There are some interesting parallels between Lowell’s Mars and Burroughs’ Barsoom, but the real question is whether or not Burroughs actually used Lowell’s map in creating Barsoom. I argue that the evidence points in that direction.

Many of Burroughs’ cities are on or near the canals shown on Lowell’s map. One might argue that there are so many canals on the map that it would be hard for this not to be the case. However, of 27 cities shown on the Bozarth map, 18 are near canals; of these only one is a “dead” city, Horz (and Horz later turns out to have inhabitants). Nine cities are not near canals, but of these nine, five are dead cities. Put another way, of 21 living cities, 17 are near canals; but of 6 dead cities, only one is near a canal. Such an arrangement seems unlikely to be due to chance. Also, in a tantalizing “coincidence”, Lowell’s canal named “Hylias”, number 227 on his map, is very close to Burroughs’ Helium.

In “Princess”, John Carter says that “The community of which the green Martians with whom my lot was cast formed a part was composed of some thirty thousand souls. They roamed an enormous tract of arid and semi-arid land between forty and eighty degrees south latitude, and bounded on the east and west by two large fertile tracts. Their headquarters lay in the southwest corner of this district, near the crossing of two of the so-called Martian canals.” Examining the Lowell map shows Thark at the southwest corner of an area bounded on the east and west by broad canals (“large fertile tracts”?) numbers 178 (Scamander) and 219 (Xanthus) on Lowell’s map. Canals 166 (Leontes) and another (182?) cross in the gray area to the southwest of Thark. When planning their escape from Thark, John Carter is told by Sola that “The great waterway which leads to Helium is but fifty miles to the south”. Later, John Carter finds another canal: “Finally, after studying the map carefully in the moonlight which now flooded the room, I pointed out a waterway far to the north of us which also seemed to lead to Helium. ‘Does not this pierce your grandfather's territory?’ I asked. ‘Yes,’  [Dejah Thoris] answered, ‘but it is two hundred miles north of us; it is one of the waterways we crossed on the trip to Thark.’" While on Lowell’s map there does not appear to be a canal “fifty miles to the south” of Thark, on the other hand there is one located about 200 miles (around 6 degrees) north of Thark, which corresponds to Lowell’s canal number 181 (Helison) a canal which does go to the location of Helium.

Many if not most of Burroughs’ cities which are on or near Lowell’s canals are also near the large spots Lowell called “oases”, described by him as “…oases in the midst of that desert, and oases not wholly innocent of design; for, in number, position, shape, and behavior, the oases turn out as typical and peculiar a feature of Mars as the canals themselves.”; but whether or not Burroughs intended his cities to lie in or on Lowell’s oases is not certain. It is possible that the cities should indeed map to the oases, but that in my transforming from a globe map such as the Bozarth map to a Mercator projection there is sufficient error to displace the cities off the intended oases. Or perhaps the error could be in Burroughs’ transposition of Lowell’s Mercator coordinates to his orthographic map, in which case a series of errors could compound: Burroughs’ transposition, Bozarth’s interpretation, and my re-transposition to Mercator coordinates. A third possibility is that Burroughs was not using Lowell’s Mercator map for his inspiration, but instead was using Lowell’s globe, one of his several orthographic maps, or his 1905 Mercator map. However, at present the actual globe is located in the Smithsonian Air and Space Museum and was not available for inspection by me. Images of that globe and other later orthographic maps, though, show only a few oases (and fewer canals) compared to the many on Lowell’s 1895 Mercator map. Lowell’s 1905 map while closer in time to the publication date of “Princess”, does not appear to be the source of inspiration: many of the 1895 canals have been relocated, old ones are gone and new ones appear, and the result is that most Barsoomian cities do not map to the 1905 canals (most tellingly, Greater and Lesser Helium are not on 1905 canals!).

Burroughs continued writing his Barsoom stories for thirty years after “Princess”, well after Lowell’s theories had been discredited and a much less favorable view of the Martian environment had emerged. Yet except for a few modern references (WWI in “The Mastermind of Mars” and “The Sultan of Swat” [Babe Ruth] in “Llana of Gathol”, for example) the environment of Barsoom remained unchanged. With the new stories, new cities had to be created, and yet even the cities which appear in the later stories largely fit the pattern described above.

So, did Burroughs use Lowell’s 1895 map in creating his Barsoom? Did he return to it periodically when writing the sequels in the Barsoom series? I think that the evidence supports this hypothesis. In the end, of course, Lowell’s canals turned out to be only ad hoc reasoning, or just plain wishful thinking. Nonetheless, who among us who has journeyed in spirit with John Carter and Tars Tarkas over the dead sea bottoms of ancient and dying Barsoom would not wish that he had been correct? In that, to my mind, lies the value of applying Lowell’s map of Mars to Burroughs’ Barsoom. It gets us closer to Barsoom as Burroughs imagined it and thus, to me at least, makes Barsoom all the more real.

~ Leathem Mehaffey
Leathem Mehaffey  Leathem Mehaffey is a professor of biology at Vassar College in Poughkeepsie, New York. A graduate of Columbia University, he did his Ph.D. in biophysics at The Ohio State University and his postdoctoral work in vision at Harvard Medical School.  Professor Mehaffey has been at Vassar since 1973, primarily teaching neurobiology and physiology. His main research interest is the cellular mechanisms of vision. 

Leathem discovered Edgar Rice Burroughs' John Carter series while a sophomore in college (he'd read his Tarzan series much earlier). He instantly fell in love with the Barsoom tales and over the years their allure has never dimmed, prompting him to return to the series many times  A couple of years ago he discovered the Yahoo Barsoom group and ERBzine and found to his delight that his interest was shared by many others. 

An avid sailor, he has always been interested in maps and navigation, so he kept a series of notes about locations of places and events on Barsoom, and recently started to put them together as a map. This led him into the possible origins of Burroughs' ideas about Mars, and that, plus the knowledge that others might be similarly interested, resulted in the accompanying article.

For more images of the maps referred to in this article
 and actual 1901 and 1908 science newstories from the Chicago Tribune see:
ERBzine 1444 and ERBzine 1445 (under construction)

Mars Map:
A Jasoomian Version of Barsoom
Modern Day Map of Mars From Huck's Barsoom Gazetteer and Glossary
ERBzine 0076 and ERBzine 0078

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ERBzine 1351

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