Department of History
University of California, Irvine
 Instructor:    Dr. Barbara J. Becker

Week 10.  Innovators and Mavericks.

Responses to Percival Lowell's Views on Mars


June 1895

Seas on Mars?
by H. Dennis Taylor

The dark zone which so closely follows up the retreating edge of the [south] polar cap of Mars as the summer advances, has usually been considered to be a belt of water resulting from the thawing of the polar snows.  But what proof have we that the white polar cap consists of snow of sufficient depth to cause such extensive inundations?...

The hypothesis which, I venture to think, best accords with the facts is suggested by the case of our own Earth, where a zone of ... vegetation of a dwarf character closely follows ... the melting of the snows....  It is this zone of vegetation, within and about the Arctic circle, which annually becomes the principal breeding ground of a very large number of migratory birds, who find their food either in the herbage and vegetation itself or else in the insects, &c., which live among it.  Such a zone [on] Mars could scarcely escape observation as a region of a darker and more greenish colour than the rest of the surface.

[W]e may assume as most likely that the greenish colour of all the darker markings of the planet is caused by the presence of vegetation growing in the more low-lying regions where there is sufficient moisture existing in the soil, while the brighter and ruddy-tinted regions are barren desert.  The observed seasonal changes in the markings would thus be accounted for.

The Rev. Edmund Ledger, in a recent lecture, discussed the absurdity of supposing that the canals could be looked upon as artificial waterways in themselves, for they must be at least 20 miles in diameter to be [seen from Earth] at all....  He suggested that they might indicate the lines of canals, the visible broadening out being due to cultivated tracts on either side of the main waterway, which should show a darker and greenish tinge.

But, if not canals, they might indicate the lines of roads cut straight across the deserts from one centre of population to another.  It would be obviously the aim of any inhabitants to make the roads as straight as possible in a nearly waterless planet.  Then, if tracts of country were cultivated and made to support vegetation, surely the districts immediately surrounding the centres of population (the dots seen where the canals intersect) would first be attended to, and afterwards substantial strips of desert at each side of the roads would be reclaimed and covered with vegetation.  This is one hypothesis which might help to explain the suspiciously artificial-looking and designed appearances of the so-called canals of Mars.


November 16, 1905

First Photographs of the Canals of Mars
by Professor Percival Lowell

To make the canals of Mars write their own record on a photographic plate, so that astronomers might have at first hand objective proof of their reality, has long been one of the objects of this observatory.  The endeavour has at last succeeded.

Unnecessary as such corroboration was to the observers themselves, it is different with the world at large; for the work of the camera at once puts the canals in a position where scientists in general, as well as astronomers in particular, are able to judge the phenomena....

After unsuccessful attempts at the last two oppositions, results were finally secured by Mr. Lampland's great skill and long-continued study of the subject....

The difficulties encountered were two-fold:  securing instrumental means of a high enough order of delicacy, and taking the photographs in such a manner as to minimise the destructive effects of the air-waves....

The photographs show that ... the canals are lines, narrow and direct, following either arcs of great circles or curving ... in a systematic manner.  In other words, the photographs prove ... what observations by the eye have asserted.

The eye is able to go much further than the camera, and the better these strange markings are seen under the best conditions ... the stranger they show.  That the camera confirms ... the eye observations at Flagstaff, should lead any unprejudiced mind to consider very seriously the probability of their being correct....

Sometimes the canals in the photographs actually appear better than they do in the drawings, though, of course, the eye is a very much more powerful instrument than the camera....  The camera must register the bad moments with the good, and details perfectly distinct to the eye must not be expected in the prints....  To produce their true effect the prints should be looked at either without further magnification or with only a very slight one, for the grain of the plate will soon destroy the true character of the detail.

-   March 12, 1904   -

Are the Canals of Mars Illusions?

In Knowledge, Mr. E. W. Maunder and Mons. E. M. Antoniadi  both contribute illustrated articles to show that the Martian Canal system, as figured by Schiaparelli and others, is largely an illusion.  Mr. Maunder has made experiments at the Royal Hospital School at Greenwich and thus describes the results:

"A class of about twenty boys, from twelve to fourteen years of age, were seated in four or five rows at different distances from a carefully-lighted diagram, which they were told to copy.  The diagram was reproduced from some published drawing of Mars, but in nearly every experiment the canals were omitted.  The diagram was generally about six inches in diameter, and the distances of the boys from the diagram ranged from fifteen to forty feet, except in two experiments where the range extended up to sixty feet....

"The general result was striking.  In several of these experiments nearly all the boys drew "canals" on their copies, though there were none on the original from which they were copying.  And these "canals" were not placed at random:  they were just in the very places where canals are seen in the charts of Schiaparelli and Lowell....

"When did the "canals" come which were drawn by the boys of the Hospital School?  One cause was the prolongation of dark indentations invading the brighter regions....  A more fruitful source of the "canals" was the introduction of regions slightly darker or slightly brighter than their surroundings....  [N]o one could wish for straighter and sharper "canals" than were drawn by a good proportion of the boys to express these regions....  But the cause which was the most effective within the limits of our experiments with the Hospital School boys was the way in which the eye summoned up together minute irregular markings, each too small to be separately perceived as straight streaks....

"The general distribution of the true markings on the planet must approximate to that shown on the charts of Schiaparelli and Lowell, and the details if not straight lines in their ultimate conceivable resolution are at least straight lines to the eye....  Lines so straight, so formal, so uniform in width, so regular in their intersections, so symmetrical, with dark spots so inevitably marking their intersections, must be accounted, as [Mr. Lowell] accounts them, artificial; the handiwork of intelligent beings.  But if actual details of perfectly irregular and unsymmetrical character, details having no sign of artificiality about them, can present exactly the appearance, and make just the impression which the network of the canal system does, the argument for the existence of inhabitants on Mars has vanished.

"We are freed, too, from the necessity of considering such bizarre theories as would make out the planet to have been scored into its present form by grazing meteorites, or to have assumed it through crystallization.  To have been set free from the grotesque in observation is to have been freed also from the grotesque in speculation.  This service I think the drawings of the Hospital School boys have effectually rendered to us.  They have shown that perfectly unbiased observers will see and draw the Schiaparellian canals when the actual markings presented to them are as little regular and artificial as any which our own earth might present to an outside spectator."

-   August 5, 1905   -


Of a bird's eye view of a world some forty millions of miles away, all that we can know are contrasts in tone and color, for the real contour of the objects must be forever masked or invisible.  In studying the planet Mars these contrasts in color and tone have to some astronomers assumed the form of lines, and, hence ... the name "canals" has been given to them.  What are these canals?  Some have suggested that they may be tracks drawn by meteorites as they have rushed along the surface....  Others have supposed that they may be fissures generally following the course of great circles, and in some parts radiating from central points.  These, it has been said, might be caused by the cracking of an unsupported crust left behind by a contracting interior; or, on the other hand, by the resistance of the interior to the contraction of a more rapidly cooling crust....

Perhaps most astronomers have been inclined to believe that the so-called canals really do not exist at all; that they are optical illusions, in a word.  What is seen is attributed to eye strain.  It must be confessed, however, that so many have observed the canals, and so many have drawn them, that their existence can hardly be doubted.  Their straightness, their immense length, which in some cases reaches 3,000 or 4,000 miles (nearly equal to the whole diameter of the planet), and their uniform and great breadth, in different instances estimated at 30, 40, or even 60 miles, would seem to augur well for their actual existence.

Perhaps the most [determined] advocate of the existence of these various canals has been Prof. Percival Lowell.  To him and to Schiaparelli we are indebted for the most minute observations of their vagaries, and to Lowell likewise for the most picturesque theories of their supposed origin.  Lowell sees in them a vast system of artificial irrigation.  But their artificial origin can hardly be maintained, when it is considered that they traverse the polar caps, and that their counterparts are to be found in Venus, Mercury, and two of the satellites of Jupiter.  That they really do exist, however, has at last been definitely proven by photography.

For a long time it has been the object of the Flagstaff Observatory, of which Prof. Lowell is the head, to photograph the enigmatic canals.  Mr. Lampland, of that observatory, has at last succeeded in accomplishing the difficult task.  Two obstacles have stood in the way of the attempt.  In the first place, fluctuating waves sometimes prevent, sometimes favor the definition of such fine detail as that of the canals.  In the second place, most photographic plates are far too slow.

Prof. Lowell determined that the attempt should be made with a bioscope film, in which many successive pictures may be taken, in the hope of securing among them one which would show the canals.  A chronophotographic apparatus was therefore devised....  Out of the many plates secured, one is here represented, dealing with the region called Syrtis Major.  Side by side with it is placed a drawing made by Prof. Lowell shortly before the camera was put on.....

The astronomical importance of this feat of photographing the canals can hardly be overestimated.  A hot controversy may now be considered definitely settled--a controversy in which most of the eminent astronomers of the world have taken part, either in absolutely denying the existence of Martian canals, or in advocating not only their existence, but also in regarding them as evidences of life on a neighboring world.

-  August 31, 1907  -


Astronomer Royal Doubts
Lowell's Theory that
Planet is Inhabited


Believes That World Was Played Out
and its Career Finished Millions
of Years Ago.

Special  Cable to THE NEW YORK TIMES.

LONDON, Aug. 30.-- Three remarkable photographs accompany Prof. Lowell's account of the observation of the planet Mars, appearing in Nature, the report of which I cabled you yesterday.  The photographs show with striking clearness the northern and southern icecaps and various canals hitherto unknown in Europe.

It was the evolution of these canals that confirmed Prof. Lowell in his theory of the presen[ce] on the planet of intelligent life.

Both the photographs and the article were the subject of interesting comment to-day at the Royal Observatory at Greenwich.  While paying high tribute to Lowell's contributions to astronomy, A. S. Eddington, F.R.S., Chief Assistant Astronomer Royal, told THE TIMES correspondent that he was not prepared yet to accept the American savant's theory as final.

"I can't quite see," said Mr. Eddington, "that Prof. Lowell has proven his case.  He has taken some wonderful photographs and they show the evolution he predicted in his work on Mars and its canals.  But we are more inclined here to accept the theory of Prof. Pickering of Harvard University, that these canals are not artificial at all, but are the result of the planet's natural shrinkage.

"This view is generally held in England, and we are inclined to believe that Mars is played out, that its career is finished.  There may have been intelligent life on the planet many millions of years ago, but this is mere speculation.  I can't quite follow Lowell when he says that because the canals evolved along predicted lines, it is a direct sequitur that the planet is at present the abode of constructive life.

"It would be quite possible to foresee certain lines of shrinkage and it would be along these lines that water would flow with the melting of the icecaps; vegetation appearing along these water courses would render them visible.  As a matter of fact, we have no right to discuss the question here, as practically all our information regarding Mars must come to us from America, as we are not situated where good observations are possible.

"For us, Mars barely rises above the treetops, so we are wholly dependent on the observations of our friends in America."

Alfred Russel Wallace, whose essay "Man's Place in the Universe," has given his name to the theory that life exists on earth only, was also asked for his opinion of Lowell's thesis.  From his country home in Dorset, Dr. Wallace telegraphs THE TIMES as follows:

"Lowell's recent observations confirm his last book, published in 1906, but the main facts are unaltered.  My own opinions are unchanged.  I am preparing for publication a book on all the questions of the climate and habitability of Mars and the probable scientific interpretation of the canals and other natural features."

The subject is variously discussed by London papers.  For example, The Daily Telegraph declares that "nothing of such profound human concern has ever before been presented on equal authority with so much definiteness and assurance."  On the other hand, The Pall Mall Gazette says, "The truth is we know too little about it to form one theory or another.  The science of astronomy waits very wistfully upon the science of telescopic photography, which declines to hurry up."

-  August 31, 1907   -


Prof. Lovett of Princeton Won't
Discuss Latest Reports

Special to The New York Times.

PRINCETON, N.J., Aug. 30.-- [E. O.] Lovett, Professor of Astronomy at Princeton University, when asked what he thought about Prof. Lowell's theory of life on Mars, said he did not care to talk about it.  If any one wanted a rejoinder to Prof. Lowell, he said, it could be found in a recent article in Popular Science by that dean of astronomers, [Simon] Newcomb.

Prof. Lovett said that Princeton had more important things to consider than the study of Mars.  "Every two years," continued the professor, "Mars is where it can be observed, and the public mind will be aroused."

-  September 28, 1907  -


For some unaccountable reason there seems to be a strong prejudice among both scientists and laymen against acknowledging the existence of a race of intelligent beings upon any planet other than our own.  We cannot help thinking that our earth is the most favorably situated of the solar system, and is the best suited to support life.  To be sure, this is so as regards life with which we are familiar; or to state it more correctly, the animal and vegetable life of this earth has adjusted itself, its habits, and its requirements, into harmony with conditions already fixed upon earth.  This is no argument that life cannot adjust itself to conditions such as are found on other planets.

Those laymen who expected that the question of life on Mars would be settled by observations during this summer's favorable opposition, were predestined to disappointment.  No one who is familiar with the subject expected as much.  It is highly improbable that we can ever prove with mathematical accuracy that animal life does exist upon the planet.  It is far easier to prove the existence of vegetable life by the seasonal changes in the color of large fields or forests.  If these areas of vegetation show any unusual configuration and arrangement such as the "oases" and "canals" or "lanes of vegetation" on Mars, it is not unreasonable to argue that the vegetation is being cultivated or regulated by a race of intelligent beings.

At the same time, the existence of such beings is not infallibly proved by such evidence.  The best that Prof. Lowell expected to do this summer was to corroborate his previous discoveries, and make further observations along the same line.  This he reports to have been successful in accomplishing.  With the aid of photography he has established beyond doubt the existence of a delicate tracery of lines on the sphere.  In addition to this, he finds that the southern hemisphere, which has heretofore been unfavorably situated for observation, is also crossed with a similar system of so-called canals.

There has been considerable criticism by prominent astronomers of the work done by Prof. Lowell as given out in his preliminary report.  In reply to this criticism, Prof. Lowell states that he is a specialist in the study of Mars, and he is better fitted than others of his own profession to judge of the conditions on that planet.  This idea of specializing in astronomy may appear to be somewhat new, although it is not at all unreasonable.  No other branch of science presents so large a field of investigation, particularly in these days of the spectroscope, which instrument permits us to come into intimate contact not only with the members of our own solar system, but with the composition and daily motions of the immeasurably distant stars.  Other sciences are divided into special branches with their acknowledged experts and specialists.  It is only reasonable to so divide the work of the astronomer.  It is not everyone who can see the canals of Mars, even through the best of telescopes.  It requires a practised eye, and one trained to this particular class of work.  The telescope which Prof. Lowell uses at the Flagstaff Observatory is not of unusual size, and is not used to the limit of its power.  It is impracticable to use a power of more than a few hundred diameters, because atmospheric disturbances are equally magnified, and to such an extent that the delicate lines on the planet are lost.  This being the case, it appears that we have about reached the limit of the possibilities of the telescope, and what further discoveries are made on the planet will be due, not to more powerful lenses, but to keeener eyesight and more experienced observation; in other words, to the work of a specialist.

-  September 30, 1907  -


While Prof. PERCIVAL LOWELL concentrates all his fine intellect and splendid energy on his investigations of the planet Mars, a large number of other astronomers and scientific writers seem to be devoting too much of their time to disproving his theories.  This is a great waste of both time and intellect.  Nobody doubts that Prof. LOWELL is working faithfully and patiently to a desired end.  To be sure, he assumes that there is animal life on Mars before he is able to prove its existence.  But as a writer in The Boston Transcript says, KEPLER divined the existence of the moons of Mars, and SWIFT and VOLTAIRE, following his lead, wrote about them, 200 years before they were actually discovered.

To say that the channels of Mars are merely optical illusions is very easy.  Any thoughtful child might jump at that concluson.  To insist that the canals, as Prof. LOWELL calls them, are lines of volcanic action, dotted with craters, is to admit the existence of the innumerable lines.  If the existence of the vegetation is also admitted, as it is by Prof. PICKERING of Harvard, and M.E.V. H[E]WARD, writing in The Fortnightly Review, the question of the existence of animal life is left open.  Where plants thrive, animals are likely to appear sooner or later.

Prof. LOWELL has the best of all the arguments about Mars, thus far, and he is in a fair way to learn a great deal more about the planet.  He is no "sensationalist" or "yellow scientist," though he is certainly an enthusiast, and probably proud of his enthusiasm.

-   October 26, 1907   -



[Percival Lowell]

The reason for looking askance at the discoveries about Mars is, of course, the old reason that man shies instinctively at the new and strange, plus the added one of his innate aversion to admitting peers.  As advances in knowledge of any import have had to contend against this spirit, as one versed in the history of science is aware.  But inasmuch as, when the theory has triumphed, one hears no more of the objections, the averagely educated man is ignorant of the discredit through which it passed.  A most interesting article could be made out of this point alone....

As to what constitutes proof, there is much popular misapprehension.  Proof of any scientific proposition is nothing more nor less than a question of probability.  Experience of nature is our only criterion of truth....  [All] of our knowledge of the cosmos ... is based on observation, and therefore on probability alone.

The mass of evidence in favor of the habitation of Mars is so strong, that emotional prejudice can attack it only by denying the facts.  Of these facts but one of many may be mentioned here, since it exemplifies the preponderance of probability spoken of.  The so-called canals are straight and very narrow lines connecting little roundish spots with mathematical precision over the whole face of the planet.  Observers with keen eyes and good atmospheric advantages agree in the detection.  Now the  chances that straight lines of the size of these should be the outcome of natural forces are millions to one, of all we know of the cosmos.  But this is far from all, and is not the special point in the matter.  If straight lines of the given length be thrown haphazard over a surface ... the chances that more than two will cross or meet at the same point are as one to infinity if the lines have no breadth, and one to an indefinitely great number if the lines ... have no perceptible breadth.

Let us consider what the chances are that lines would exactly connect certain centers if they were not directed to that end.  We will take two spots 600 miles apart as fairly averaging the Martian conditions; with the lines, the canals, 15 miles wide.  Conceive, to put the case as favorably as possible for the side of natural forces, that the spots were themselves decided by explosions there giving out radiating lines.  Now, what is the chance that one of these lines would hit another spot?

Think of a square 600 miles in diameter about one of the spots, and take as a mean of the Martian state of things that six lines radiate from each spot; the lines being each 600 miles long and the spots equally distributed over the planet and themselves 30 miles in diameter....  From the observations it is evident that if the lines did not strike the oasis or spot within 15 miles on either side the center, the inexactness would be visible.  A line therefore must hit an area 30 miles across at a distance of 600 miles.  Its range of variation in direction to come within the limits is therefore a little less than 3 deg.  But as it may radiate out anywhere round the entire circle of 360 deg., the chance that it will strike the spot is 3/360 or 1/120.  As there are six radiating lines, the chance that one out of the six does so is 6/120....  That all six lines from the first spot should [each in a similar fashion] strike ... surrounding spots, the chances are:  6/120 X 5/120 X 4/120 X 3/120 X 2/120 X 1/120 or 1/24,110,000,000; that is, 24 billions to one....  For the chance that 200 [such] spots should be thus interconnected is (3/120 X 2/120 X 1/120)200, or as one to sixteen with 259 ciphers after it!  For this reason no mathematician could for a moment suppose them to be cracks, but unfortunately most laymen and many astronomers, contrary to popular misapprehension, are not mathematicians.

Reversely, this enormous number to one is the chance that the lines are the outcome of a definite underlying plan not due to natural causes, unless we suppose natural causes of which we have no cognizance, and therefore no specific right to call in.  The whole aim and action of science is to explain; it is only [ignorance] that summons the unknown to its aid.  But here we have an explanation at hand able and sufficient, to wit:  local intelligence on the planet directing the position of these lines.  This takes the place in our present inquiry that the law of gravitation does in the movement of the planets, and in both the mathematical chances in its favor are so overwhelming as to constitute what we mean by saying a thing is proved.  I have mentioned here but one line of evidence; many more will be found in "Mars and Its Canals," all converging to the same conclusion.  No assumption of life is made there, but preponderances of probability are massed one upon another to show it, which is precisely what we pronounce proof.

-   November 5, 1907   -


Prof. Lowell's Estimate of Pictures
Just Received from
the Andes Expedition


Photographs and Drawings Are to be
Exhibited in this City

Special to the New York Times.

FLAGSTAFF, Ariz., Nov. 4-- At the requst of THE NEW YORK TIMES, Prof. Lowell wires that E. C. Slipper [Slipher] of the observatory staff at Flagstaff has just arrived there from the expedition to the Andes, bringing the results.

As all the Mars work of the expedition, both in the matter of drawings and photographs, was done solely by Mr. Slipper, furnished with the special apparatus, and familiarized beforehand with the subject, the excellent manner in which he did that work has added most satisfactorily to our knowledge of the planet.

A preliminary inspection of the results proves them of great value and entirely corroborative of Prof. Lowell's theory of intelligent life on Mars.  One of the most striking details in Mr. Slipper's drawings is the darker right side of the double ganglia, a phenomenon discovered at Flagstaff in 1905, and having important bearing on the meaning of the double canals.  The peculiarity was unknown to Mr. Slipper at the time he made his drawings.

Several new canals in addition to those already known have been discovered by him, and a great many doubles observed, thus testifying to the remarkable steadiness of the air for Mars work, which was the object of the expedition.

Both photographs and drawings will be exhibited through the courtesy of Prof. Osborn at the American Museum of Natural History in New York.

-   November 8, 1907   -


Prof. PERCIVAL LOWELL, whose Martian investigation has been described in a lecture at Columbia University by Prof. HAROLD JACOBY as "inartistic research," may take comfort from the fact that Prof. JACOBY, in the same lecture, attacked NEWTON and declared that "all the intricacies of motion can be explained just as well by PTOLEMY'S theory" as by NEWTON'S, which may "pass entirely out of use."  That is to say, Prof. LOWELL may find this consolation, if he bothers at all about adverse opinions of his work, which is doubtful.  He is too deeply interested in his examination of the canals of Mars and his theories as to their uses to bother about what folks are saying.

Prof. JACOBY is an astronomer who thinks the so-called Martian canals--"a rather hazy marking" some observers think they see--are optical illusions.  JACOBY, and others like him, do not believe there is life on Mars, but they cannot prove what they say.  Their arguments are purely negative.

Prof. LOWELL has the best of them.  He knows the canals and can identify them .  He notes their harmonious design and sees in them the proof of a great living intelligence.  We not only sympathize with Prof. LOWELL, but we envy him.

"How Much Water Can There Be on Mars?"
Miss Agnes M. Clerke
cited in Is Mars Habitable? (1907), by Alfred Russel Wallace

There is every reason to believe that the Martian snow-caps are quite flimsy structures.  Their material might be called snow soufflé, since, owing to the small power of gravity on Mars, snow is almost three times lighter there than here....

No attempt has yet been made to estimate the quantity of water derivable from the melting of one of these formations; yet the experiment is worth trying as a help towards defining ideas.

Let us grant that the average depth of snow in them, of the delicate Martian kind, is twenty feet, equivalent at the most to one foot of water.

The maximum area covered, of 2,400,000 square miles, is nearly equal to that of the United States, while the whole globe of Mars measures 55,500,000 square miles of which one-third, on the present hypothesis, is under cultivation, and in need of water....  That is to say, they cover an area, in round numbers, seven times that of the snow-cap.

Only one-seventh of a foot of water ... could possibly be made available for their fertilisation, supposing them to get the entire advantage of the spring freshet.  Upon a stint of less than two inches of water these fertile lands are expected to flourish and bear abundant crops....

We have assumed, in our little calculation, that the entire contents of a polar hood turn to water; but in actual fact a considerable proportion of them must pass directly into vapour.

-   March 21, 1908   -



A telegram from the Lowell Observatory, Flagstaff, Ariz., recently announced the discovery that the atmosphere of Mars is very rich in water vapor.  This information gained by Mr. Slipher from a comparison of the spectra of Mars and the moon, is one of the most important additions to astronomical knowledge that has been attained in recent years.  The solution of the question of water in the atmosphere of the much discussed planet demands the very best observational facilities and the most careful attention to all the minutest details that make up a delicate research.  In short, it may be said that this problem is one of the most difficult of solution in the whole of astronomy, a science remarkably full of knotty questions.  The importance of this latest discovery can hardly be overestimated, for it may almost be said that the whole question of human life on our neighbor hinges on whether the atmosphere of Mars is dry or whether it is saturated with a plentiful supply of the vapor of water; and realizing this, astronomers have been trying now for forty-five years to settle this very problem.

Mars and its canals is all-engrossing to the scientific world at the present time.  The near approach during the summer of 1907 has given astronomers after an interval of fifteen years an opportunity to re-attack Mars with improved observational means, especially by the application of the sensitive photographic plate.  The Lowell expedition to the Andes for the purpose of photographing Mars was a magnificent piece of scientific research, and Mr. Lowell is to be heartily congratulated upon the success of his photographic work, both in the Andes and in the parent observatory at Flagstaff.  The photographs are superb and of excellent definition, and, as a matter of fact, far surpass any that have ever hitherto been taken.  Strange as it may seem to the outside world, these photographs have not at all settled the question of the habitability of Mars; for, magnificent as they are in detail, it must not be forgotten that the largest of the Lowell photographs are but a scant three-sixteenths of an inch in diameter, and that no detail is added by putting them under a powerful microscope.

The astronomical world is divided into three over the question of Mars and its canals.  On one side we have Mr. Lowell and his followers, who by visual observations with the telescope and the recent photographs have discovered the presence of hundreds of thin line markings aggregating thousands of miles in length.  The remarkable straightness of these canals, their systematic arrangement, and the changes that have been noted in their appearance at different seasons, have proved to Mr. Lowell that these canals are the result of human ingenuity, and that their purpose is to irrigate the desert planet and render it fit for human habitation.  Conclusive as these arguments seem to be to the observers at Flagstaff, the majority of the first-class astronomers in the world do not agree with them.  On the one hand we have the highly-trained observers at the Lick and Yerkes observatories --where telescopes are bigger than Mr. Lowell's, and where the seeing, especially at the Lick, is probably just as good as at Flagstaff--who have not altogether succeeded in seeing all that Mr. Lowell has seen, though indeed a considerable amount of planetary detail has been observed.  And on the other hand there are a great number of astronomers who see thin fine markings when they observe Mars, but who state that they are due to a physiological defect in the eye.  This latter idea has been championed by Maunder of England, and lately in a very excellent way by our own Prof. Simon Newcomb.  So that Prof. Lowell is practically alone in the astronomical world in believing that he has proven that Mars is inhabited.

Sir David Gill, the former Astronomer Royal at the Cape of Good Hope, one of the greatest living astronomers, after examining the latest photographs of Prof. Lowell, spoke a few days ago in a lecture at the Royal Institute in London in the following manner:  "I see nothing even resembling evidence of human work.  I do not deny the possibility of the existence of some sort of animal very different from ourselves, but I see no proof of the work of sentient human beings on the enormous scale that has been talked about."

Though there is this wide divergency of opinion regarding the canals and their meaning, there is perfect unanimity regarding many features of the ruddy planet.  In an exact science like astronomy, the question of the attraction of gravity on the surface of Mars can have only one answer:  It is 0.38 that of the earth.  All are agreed that Mars is very flat; no mountains have ever been seen by anybody.  All astronomers are a unit in believing that there is remarkably little water on Mars, that the dark areas are not "seas" as was first supposed, and that the only water ever claimed to have been seen on Mars is that immediately surrounding the polar ice caps as the snow and ice melts in the Martian summer.  In fact, it is this very scarcity of water that makes it necessary to have irrigating canals, in order that life may be sustained.

The small attraction of gravity seems in the opinion of all astronomers to demand as a consequence that the atmosphere be very rare, somewhat comparable to that on the lofty peaks of the Himalaya Mountains.  Day after day, week after week, the Martian landscape is unobstructed by the presence of any clouds except those of an occasional sandstorm blowing over the barren deserts, no clouds, like those of our own atmosphere, have ever been seen.

This absence of clouds and the rarity of atmosphere have most important bearings on the question of life on the planet.  If the air at the surface of Mars is as tenuous as that at the tops of our highest mountains, what about the temperature?  Should everything then be snow-capped as on the earth?  And the temperature below freezing?  For this interesting question we have no sure answer, but it has seemed to all investigators that the temperature must be quite low.  In addition to the rarity of its atmosphere, Mars is farther away from the sun than the earth, and gets only one-half as much heat.  Then, too, Mars is probably an older planet, and, as it is also smaller, has less internal heat than the earth.  Looked at from all points of view, Martian weather must be very cold.... [A]ll our knowledge points to the fact that if the atmosphere on Mars at all resembles our own, it should then be always below freezing.  To have water in the canals and above freezing point, it is necessary to assume that the atmosphere differs radically from our own.

If with Prof. Lowell we postulate an atmosphere with a copious supply of aqueous vapor, the difficulties of temperature will probably disappear.  Water in the atmosphere will act like the glass in a greenhouse, will let the sun's rays in, but will entrap them as they are radiated back, and Mars may thus really have a temperature capable of supporting life.  How are we going to discover the presence of this water vapor?  It cannot be done by direct telescopic observation.  The atmosphere is very rare, and the water vapor for some reason does not seem to condense into clouds.  Recourse must be had to the all-powerful spectroscope, which has already settled so many strange problems in astronomy.

The laws underlying spectrum analysis were understood for the first time in 1859....  Only three years later Rutherfurd of New York and Huggins of London, pioneers in this new astronomy, investigated the spectrum of Mars, in order to see if its red color was not due to great absorption in its atmosphere.  How has their work been done?  And to what conclusions have they come?

As is well known, the spectroscope tells us the chemical constitution of the sun by comparing its spectrum with that of [a known element] and noting the coincidences of the lines in the two spectra.  The solar spectrum consists of a bright band of all colors crossed by thousands of dark lines called, after their discoverer, Fraunhofer lines.  The principles which enter into the application of the spectroscope to Mars are readily understood.  The planet, we know, shines by reflected sunlight.  Its spectrum, therefore, must be identical with that of the sun except as it is modified by the (supposed) atmosphere of Mars....

Nearly all the early investigators of the spectrum of Mars thought that its atmosphere very much resembles our own, differing mainly in being richer in water vapor....  Prof. Campbell at the Lick Observatory reached the conclusion that the spectrum of Mars is identical with that of the moon, and that consequently nothing is known of the atmosphere of Mars....

From a different line of reasoning Mr. Jewell, of the Johns Hopkins University, decides that it is useless to attack this problem until the instrumental equipment is far superior to any that has hitherto been used.  Consequently, this seems to be one of the problems for the future to decide; its solution seems unattainable at the present time.  The spectroscope settles its problems by the position, character, or intensity of a line or lines among thousands in the spectrum.  Marvelous have been its triumphs and wonderful the results attained, such as determining the chemical constitution of the sun or distant stars, measuring the motion in the line of sight of stars millions and millions of miles away, or fixing the nature of the rings of Saturn, but these triumphs have been reached only along a pathway strewn with countless mistakes in measuring the position of a line or in wrongly interpreting its meaning, so that in spectroscopic study it is well to make haste slowly....

[However] a desert planet, barren and desolate, on which life would be impossible were it not for irrigation, but one which is wafted by an atmosphere laden with water vapor, seems to be an anomaly difficult to understand!

Letters from
William Huggins
(amateur astronomer; 1824-1910)

to Joseph Larmor
(physicist and mathematician, secretary of the Royal Society; 1857-1942)

on the Subject of Mars

September 10, 1908

I wonder Percival Lowell does not avail himself of Ra[dium] to warm up Mars.  Why may not the planet be very rich in Ra[dium], Ur[anium], and other heat giving substances?


November 20, 1908

[I hear] that even with a large telescope Mars & Jupiter can only be seen under conditions similar to viewing the moon through a [small one] (!) and that no real details can be possibly discovered on their surfaces.  The appearances seen are pseudo-ones, and may be utterly unlike the real ones....


February 28, 1910

While Lowell is preaching the great engineering feats of the Martians in the making of new canals, the opinion among astronomers has greatly strengthened, from the observations at the present opposition*, that there are no canals!

*opposition:  when a planet is located directly opposite the Sun in Earth's sky; the best time for earthbound viewers to observe the planet.


All fools' day 1910

Lowell has gone over to Paris to lecture.  He professes to be able to see defined images of telegraph wires subtending only 4/100 of the angle supposed to be necessary....

Of course I stand up for water, as I have a Sea in Mars [see "Huggins Inlet" on map below], and am expecting to become passing rich from royalties on Martian fish....!**

**Do you think William Huggins has changed his mind about the possibility of canals on Mars?  What day was this letter written?

"Huggins Inlet" shown on "A Chart of Mars" by Richard Proctor (1867)

Go to:
  • Mars (1895), by Percival Lowell (1855-1916)
  • Arguments FOR and AGAINST the Artificiality of the Visible Features on the Planet Mars
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