There is some reason to believe the so-called seas of Mars to have been seas in their day, and to be at the present moment midway in evolution from the seas of Earth to the seas of the Moon.

Now, if a planet were at any stage of its career able to support life, it is probable that a diminishing water supply would be the beginning of the end of that life, for the air would outlast the available water. 

Those of its inhabitants who had succeeded in surviving would find themselves at last face to face with the relentlessness of a scarcity of water constantly growing greater, till at last they would all die of thirst, either directly or indirectly.... 

Before this lamentable conclusion was reached, however, there would come a time ... when, for the inhabitants, the one supreme problem of existence would be the water problem, -- how to get water enough to sustain life, and how best to utilize every drop of water they could get.

Mars is, apparently, in this distressing plight at the present moment, the signs being that its water supply is now exceedingly low.  If, therefore, the planet possess inhabitants, there is but one course open to them in order to support life.  Irrigation, and upon as vast scale as possible, must be the all-engrossing Martian pursuit.

Sir William Huggins' ... opinion at the present time is that "there is no conclusive proof of the presence of [water] vapour in the atmosphere of Mars, and the observations at the Lick Observatory (in 1895), where the conditions and instruments are of the highest order, were negative...."

If there were any [excess] water derived from the melting snow ... any attempt to make that scanty surplus, by means of overflowing canals, travel ... through such a terrible desert region ... exposed to such a cloudless sky as Mr. Lowell describes, would be the work of a body of madmen rather than of intelligent beings.  It may be safely asserted that not one drop of water would escape evaporation or insoak at even a hundred miles from its source....

At the very lowest estimate the total length of the canals observed and mapped by Mr. Lowell must be over a hundred thousand miles ... and thus we are led to a system of irrigation of almost unimaginable magnitude on a planet which has no mountains, no rivers, and no rain to support it; whose whole water-supply is derived from polar snows, the amount of which is ludicrously inadequate to need any such world-wide system; while the low atmospheric pressure would lead to rapid evaporation, thus greatly diminishing the small amount of moisture that is available....

[Mr. Lowell] dwells, emphatically, on the terrible desert conditions of the greater part of the surface of [Mars].  That being the case now, we have no right to assume that it has ever been otherwise; and, taking full account of the fact, neither denied nor disputed by Mr. Lowell, that the force of gravity on Mars is not sufficient to retain water-vapour in its atmosphere, we must conclude that the surface of that planet, like that of the moon, has been moulded by some form of volcanic action modified probably by wind, but not by water....

The absence of water is of itself conclusive against the existence of animal life, unless we enter the regions of pure conjecture as to the possibility of some other liquid being able to take its place, and that liquid being as omnipresent there as water is here.

Mars (30° longitude), drawing by Percival Lowell

What confronts us is this:--

When the great continental areas, the reddish-ochre portions of the disk, are attentively examined in sufficiently steady air, their desert-like ground is seen to be traversed by a network of fine, straight, dark lines. 

The lines start from points on the coast of the blue-green regions, commonly well-marked bays, and proceed directly to what seem centres in the middle of the continent, since most surprisingly they meet there other lines that have come to the same spot with apparently a like determinate intent.  And this state of things is not confined to any one part of the planet, but takes place all over the reddish-ochre regions.

The lines appear either absolutely straight from one end to the other, or curved in an equally uniform manner.  There is nothing haphazard in the look of any of them.  Plotting upon a globe betrays them to be arcs of great circles....

The lines are as fine as they are straight.  As a rule, they are of scarcely any perceptible breadth, seeming on the average to be less than ... about thirty miles wide....  Their length is usually great, and in cases enormous.  A thousand or fifteen hundred miles may be considered about the average.

[The earth itself is not] devoid of 'straight lines' structurally produced....  Examples of these are the numerous 'faults' which occur in the harder rocks, and which often extend for great distances in almost perfect straight lines. 

In [England] we have the Tyneside and Craven faults ... which are 30 miles long and often 20 yards wide; but even more striking is the great Cleveland Dyke -- a wall of volcanic rock dipping slightly toward the south, but sometimes being almost vertical, and stretching across the country, over hill and dale, in an almost perfect straight line  ... a distance of very nearly 60 miles.  The great fault between the Highlands and Lowlands of Scotland extends ... a distance of 120 miles....

Much more extensive are some of the great continental dislocations often forming valleys of considerable width and length.  The Upper Rhine flows in one of these great valleys ... for about 180 miles ... in a generally straight line....  Vaster still is the valley of the Jordan through the Sea of Galilee ... to the Gulf of Akaba, believed to form one vast ... fracture extending in a straight line for 400 miles.

The reason that so few astronomers have as yet succeeded in seeing these lines is to be found in our own atmosphere.  That in ordinary atmosphere the lines are not easy objects is certain.  A moderately good air is essential to their detection; and unfortunately the locations of most of our observatories preclude this prerequisite.  Size of the telescope used is a very secondary matter.... 

The importance of atmosphere in the study of planetary detail is far from being appreciated.  It is not simply question of a clear air, but of a steady one.  To detect fine detail, the atmospheric strata must be as evenly disposed as possible.

Next in importance to a steady air comes attentive perception on the part of the observer....  Revelations of detail come only to those who patiently watch for the few good moments among the many poor....  For the canals to come out in all their fineness and geometrical precision, the air must be steady enough to show the markings on the planet's disk with the clear-cut character of a steel engraving.  No one who has not seen the planet thus can pass upon the character of these lines.

In 1894, after a careful search for the best atmospheric conditions, Mr. Lowell established his observatory near the town of Flagstaff in Arizona, in a very dry and uniform climate, and at an elevation of 7300 feet above the sea.  He then possessed a fine equatorial telescope of 18 inches aperture....  He thus became perhaps more favourably situated than any astronomer in the northern hemisphere, and during the last twelve years has made a specialty of the study of Mars, besides doing much valuable astronomical work on other planets....

No one can read [Mr. Lowell's] book without admiration for the extreme perseverance in long continued and successful observation, the results of which are here recorded; and I myself accept unreservedly the substantial accuracy of the whole series....

But though I wish to do the fullest justice to Mr. Lowell's technical skill and long years of persevering work, which have brought to light the most complex and remarkable appearances that any of the heavenly bodies present to us, I am obliged absolutely to part company with him as regards the startling theory of artificial production which he things alone adequate to explain them.  So much is this the case, that the very phenomena, which to him seem to demonstrate the intervention of intelligent beings working for the improvement of their own environment, are those which seem to me to bear the unmistakeable impress of being due to natural forces, while they are wholly unintelligible as being useful works of art.  I refer of course to the great system of what are termed 'canals,' whether single or double.  Of these I shall give my own interpretation later on.

Mars (60° longitude), drawing by Percival Lowell

It is patent that here are phenomena that are passing strange.  To read their riddle we had best begin by excluding what [the canals] are not, as help towards deciphering what they are....

To any one who had not seen the canals, it might occur that something [like this could be caused] by cracks radiating from centres of explosion or fissure....  We see examples of what might result from such action in the cracks that radiate from [the crater] Tycho, in the Moon....  These cracks bear no resemblance whatever to the lines on Mars.  They look like cracks; the lines on Mars do not.  Indeed., it is safe to say that the Martian lines would never so much as suggest cracks to any one....

They cannot, for example, be rivers; for rivers could not be so obligingly of the same size at source and mouth, nor would they run from preference on arcs of great circles....  Glaciations cracks are equally out of the question....  Nor can the lines be furrows ploughed by meteorites,--another ingenious suggestion,--since, in order to plough, invariably, a furrow straight from one centre to another, without either missing the mark or overshooting it, the visitant meteorite would have to be specially trained to the business.

[Assume Mars has] an outer layer of moderate thickness ... which would have cooled from a highly heated state to a temperature considerably below the freezing-point, and this would have been all the time contracting upon a previously cold, and therfore non-contracting nucleus. 

The result would be that very early in the process great superficial tensions would be produced, which could only be relieved by cracks or fissures, which would initiate at points of weakeness ... from which they would radiate in several directions.  Each crack thus formed near the surface would, as cooling progressed, develop in length and depth; and owing to the general uniformity of the material, and possibly some amount of crystalline structure ... the cracks would tend to run on in straight lines and to extend vertically downwards....

Mars (120° longitude), drawing by Percival Lowell

As, in observations of minute detail, the psychic element insensibly creeps in, it will be well to consider it for a moment.  An idea is a force, a mode of motion, which, unless obstructed by other ideas, instantly and inevitably produces its effect upon whatever mind it may chance to impinge, just as light or electricity or any other mode of motion does, according to its kind....

Our senses are our avenues of approach from the outer world.  Messages from them are therefore usually and rightly attributed to stimuli from without.  But it is possible for these messages to be tampered with at any stage of their journey.  It is even possible for them to be started in some other part of the brain, travel down to the lower centres and be sent up from them to the higher ones, indistinguishable from bona fide messages from without.  Bright points in the sky or a blow on the head will equally cause one to see stars....

We easily see what we expect to see, but with great difficulty what we do not.

Few persons except astronomers fully realise that of all the planets of the Solar system the only one whose solid surface has been seen with certainty is Mars; and, very fortunately, that is also the only one which is sufficiently near to us for the physical features of the surface to be determined with any accuracy.... 

The most obvious peculiarity of this planet -- its polar snow-caps -- were seen about 250 years ago, but they were first proved to increase and decrease alternately, in the summer and winter of each hemisphere ... in the latter part of the eighteenth century. 

This fact gave the impulse to the idea of similarity in the conditions of Mars and the earth, which the recognition of many large dusky patches and streaks as water, and the more ruddy and brighter portions as land, further increased. 

Added to this, a day only about half an hour longer than our own, and a succession of seasons of the same character as ours but of nearly double the length ... seemed to leave little wanting to render this planet a true earth on a smaller scale.  It was therefore very natural to suppose that it must be inhabited, and that we should some day obtain evidence of the fact....

The one great feature of Mars which led Mr. Lowell to adopt the view of its being inhabited by a race of highly intelligent beings ... is undoubtedly that of the so-called 'canals' -- their straightness, their enormous length, their great abundance, and their extension over the planet's whole surface from one polar snow-cap to the other. 

The very immensity of this system, and its constant growth and extension during fifteen years of persistent observation, have so completely taken possession of his mind, that, after a very hasty glance at analogous facts and possibilities, he has declared them to be 'non-natural' -- therefore to be works of art -- therefore to necessitate the presence of highly intelligent beings who have designed and constructed them. 

This idea has coloured or governed all his writings on the subject.  The innumerable difficulties which it raises have been either ignored, or brushed aside on the flimsiest evidence. 

Mars (210° longitude), drawing by Percival Lowell

We find, in the first place, that the broad physical conditions of the planet are not antagonistic to some form of life; secondly, that there is an apparent dearth of water upon the planet's surface, and therefore, if begins of sufficient intelligence inhabited it, they would have to resort to irrigation to support life; thirdly, that there turns out to be a network of markings covering the disk precisely counterparting what a system of irrigation would look like; and, lastly, that there is a set of spots placed where we should expect to find the lands thus artificially fertilized, and behaving as such constructed oases should. 

All this, of course, may be a set of coincidences, signifying nothing; but the probability points the other way.  As to details of explanation, any we may adopt will undoubtedly be found, on closer acquaintance, to vary from the actual Martian state of things; for any Martian life must differ markedly from our own....

To talk of Martian beings is not to mean Martian men....  Amid the surroundings that exist on Mars, surroundings so different from our own, we may be practically sure other organisms have been evolved of which we have no cognizance.  What manner of beings they may be we lack the data even to conceive.

For answers to such problems we must look to the future.  That Mars seems to be inhabited is not the last, but the first word on the subject.  More important than the mere fact of the existence of living beings there, is the question of what they may be like.  Whether we ourselves shall live to learn this cannot, of course, be foretold.  One thing, however, we can do, and that speedily:  look at things from a standpoint raised above our local point of view; free our minds at least from the shackles that of necessity tether our bodies; recognize the possibility of others in the same light that we do the certainty of ourselves....

If astronomy teaches us anything, it teaches that man is but a detail in the evolution of the universe, and that resemblant though diverse details are inevitably to be expected in the host of orbs around him.  He learns that, though he will never find his double anywhere, he is destined to discover any number of cousins scattered through space.

If a theory be correct, it will not only fit all the facts, but at times go out of its way to answer questions.

[Mr. Lowell] never even discusses the totally inadequate water-supply for such world-wide irrigation, or the extreme irrationality of constructing so vast a canal-system the waste from which, by evaporation, when exposed to such desert conditions as he himself describes, would use up ten times the probably supply.

Again, he urges the 'purpose' displayed in these 'canals.' Their being all so straight, all describing great circles of the 'sphere,' all being so evidently arranged (as he things) either to carry water to some 'oasis' 2000 miles away, or to reach some arid region far over the equator in the opposite hemisphere! 

But he never considers the difficulties this implies.  Everywhere these canals run for thousands of miles across waterless deserts, forming a system and indicating a purpose, the wonderful perfection of which he is never tired of dwelling upon (but which I myself can nowhere perceive). 

Yet he never even attempts to explain how the Martians could have lived before this great system was planned and executed, or why they did not first utilise and render fertile the belt of land adjacent to the limits of the polar snows--why the method of irrigation did not, as with all human arts, begin gradually, at home, with terraces and channels to irrigate the land close to the source of the water. 

How, with such a desert as he describes three-fourths of Mars to be, did the inhabitants ever get to know anything of the equatorial regions and its needs, so as to start right away to supply those needs? 

All this, to my mind, is quite opposed to the idea of their being works of art, and altogether in favour of their being natural features of a globe as peculiar in origin and internal structure as it is in its surface-features. 

The explanation I have given, though of course hypothetical, is founded on known cosmical and terrestrial facts, and is, I suggest, far more scientific as well as more satisfactory than Mr. Lowell's wholly unsupported speculation....

Mr. Lowell never even refers to the important question of loss by evaporation in these enormous open canals, or considers the undoubted fact that the only intelligent and practical way to convey a limited quantity of water such great distances would be by a system of water-tight and air-tight tubes laid under the ground.  The mere attempt to use open canals for such a purpose shows complete ignorance and stupidity in these alleged very superior beings; while it is certain that, long before half of them were completed their failure to be of any use would have led any rational beings to cease constructing them.

He also fails to consider the difficulty, that, if these canals are necessary for existence in Mars, how did the inhabitants ever reach a sufficiently large population with surplus food and leisure enabling them to rise from the low condition of savages to one of civilisation, and ultimately to scientific knowledge?  Here again is a dilemma which is hard to overcome.  Only a dense population with ample means of subsistence could possibly have constructed such gigantic works; but, given these two conditions, no adequate motive existed for the conception and execution of them -- even if they were likely to be of any use.

Mars, therefore, is not only uninhabited by intelligent beings such as Mr. Lowell postulates, but is absolutely UNINHABITABLE.