THE PLANET MARS.
BY GIOVANNI SCHIAPARELLI.
Many of the first astronomers who studied Mars with the telescope hadnoted on the outline of its disk two brilliant white spots of roundedform and of variable size. In process of time it was observed that whilethe ordinary spots upon Mars were displaced rapidly in consequence ofits daily rotation, changing in a few hours both their position andtheir perspective, the two white spots remained sensibly motionless attheir posts. It was concluded rightly from this that they must occupythe poles of rotation of the planet, or at least must be found very nearto them. Consequently they were given the name of polar caps or spots.And not without reason is it conjectured that these represent upon Marsthat immense mass of snow and ice which still to-day prevents navigatorsfrom reaching the poles of the earth. We are led to this conclusion notonly by the analogy of aspect and of place, but also by anotherimportant observation....
As things stand, it is manifest that if the above-mentioned white polarspots of Mars represent snow and ice they should continue to decrease insize with the approach of summer in those places and increase during thewinter. Now this very fact is observed in the most evident manner. Inthe second half of the year 1892 the southern polar cap was in fullview; during that interval, and especially in the months of July andAugust, its rapid diminution from week to week was very evident even tothose observing with common telescopes. This snow (for we may well callit so), which in the beginning reached as far as latitude 70 degrees andformed a cap of over 2,000 kilometers (1,200 miles) in diameter,progressively diminished, so that two or three months later little moreof it remained than an area of perhaps 300 kilometers (180 miles) at themost, and still less was seen in the last days of 1892. In these monthsthe southern hemisphere of Mars had its summer, the summer solsticeoccurring upon October 13. Correspondingly the mass of snow surroundingthe northern pole should have increased; but this fact was notobservable, since that pole was situated in the hemisphere of Marswhich was opposite to that facing the earth. The melting of the northernsnow was seen in its turn in the years 1882, 1884 and 1886.
These observations of the alternate increase and decrease of the polarsnows are easily made even with telescopes of moderate power, but theybecome much more interesting and instructive when we can followassiduously the changes in their more minute particulars, using largerinstruments. The snowy regions are then seen to be successively notchedat their edges; black holes and huge fissures are formed in theirinteriors; great isolated pieces many miles in extent stand out from theprincipal mass and, dissolving, disappear a little later. In short, thesame divisions and movements of these icy fields present themselves tous at a glance that occur during the summer of our own arctic regions,according to the descriptions of explorers.
The southern snow, however, presents this peculiarity: The center of itsirregularly rounded figure does not coincide exactly with the pole, butis situated at another point, which is nearly always the same, and isdistant from the pole about 300 kilometers (180 miles) in the directionof the Mare Erythraeum. From this we conclude that when the area of thesnow is reduced to its smallest extent the south pole of Mars isuncovered, and therefore, perhaps, the problem of reaching it upon thisplanet is easier than upon the earth. The southern snow is in the midstof a huge dark spot, which with its branches occupies nearly one-thirdof the whole surface of Mars, and is supposed to represent its principalocean. Hence the analogy with our arctic and antarctic snows may be saidto be complete, and especially so with the antarctic one.
The mass of the northern snow cap of Mars is, on the other hand,centered almost exactly upon its pole. It is located in a region ofyellow color, which we are accustomed to consider as representing thecontinent of the planet. From this arises a singular phenomenon whichhas no analogy upon the earth. At the melting of the snows accumulatedat that pole during the long night of ten months and more the liquidmass produced in that operation is diffused around the circumference ofthe snowy region, converting a large zone of surrounding land into atemporary sea and filling all the lower regions. This produces agigantic inundation, which has led some observers to suppose theexistence of another ocean in those parts, but which does not reallyexist in that place, at least as a permanent sea. We see then (the lastopportunity was in 1884) the white spot of the snow surrounded by adark zone, which follows its perimeter in its progressive diminution,upon a circumference ever more and more narrow. The outer part of thiszone branches out into dark lines, which occupy all the surroundingregion, and seem to be distributary canals by which the liquid mass mayreturn to its natural position. This produces in these regions veryextensive lakes, such as that designated upon the map by the name ofLacus Hyperboreus; the neighboring interior sea called Mare Acidaliumbecomes more black and more conspicuous. And it is to be remembered as avery probable thing that the flowing of this melted snow is the causewhich determines principally the hydrographic state of the planet andthe variations that are periodically observed in its aspect. Somethingsimilar would be seen upon the earth if one of our poles came to belocated suddenly in the center of Asia or of Africa. As things stand atpresent, we may find a miniature image of these conditions in theflooding that is observed in our streams at the melting of the Alpinesnows.
Travellers in the arctic regions have frequent occasion to observe howthe state of the polar ice at the beginning of the summer, and even atthe beginning of July, is always very unfavorable to their progress.The best season for exploration is in the month of August, and Septemberis the month in which the trouble from ice is the least. Thus inSeptember our Alps are usually more practicable than at any otherseason. And the reason for it is clear--the melting of the snow requirestime; a high temperature is not sufficient; it is necessary that itshould continue, and its effect will be so much the greater, as it isthe more prolonged. Thus, if we could slow down the course of our seasonso that each month should last sixty days instead of thirty, in thesummer, in such a lengthened condition, the melting of the ice wouldprogress much further, and perhaps it would not be an exaggeration tosay that the polar cap at the end of the warm season would be entirelydestroyed. But one cannot doubt, in such a case, that the fixed portionof such a cap would be reduced to a much smaller size, than we see itto-day. Now, this is exactly what happens to Mars. The long year, nearlydouble our own, permits the ice to accumulate during the polar night often or twelve months, so as to descend in the form of a continuous layeras far as parallel 70 degrees, or even farther. But in the day whichfollows, of twelve or ten months, the sun has time to melt all, ornearly all, of the snow of recent formation, reducing it to such asmall area that it seems to us no more than a very white point. Andperhaps this snow is entirely destroyed; but of this there is at presentno satisfactory observation.
Other white spots of a transitory character and of a less regulararrangement are formed in the southern hemisphere upon the islands nearthe pole, and also in the opposite hemisphere whitish regions appear attimes surrounding the north pole and reaching to 50 degrees and 55degrees of latitude. They are, perhaps, transitory snows, similar tothose which are observed in our latitudes. But also in the torrid zoneof Mars are seen some very small white spots more or less persistent;among others one was seen by me in three consecutive oppositions(1877-1882) at the point indicated upon our chart by longitude 268degrees and latitude 16 degrees north. Perhaps we may be permitted toimagine in this place the existence of a mountain capable of supportingextensive ice fields. The existence of such a mountain has also beensuggested by some recent observers upon other grounds.
As has been stated, the polar snows of Mars prove in an incontrovertiblemanner that this planet, like the earth, is surrounded by an atmospherecapable of transporting vapor, from one place to another. These snowsare, in fact, precipitations of vapor, condensed by the cold, andcarried with it successively. How carried with it if not by atmosphericmovement? The existence of an atmosphere charged with vapor has beenconfirmed also by spectroscopic observations, principally those
ofVogel, according to which this atmosphere must be of a compositiondiffering little from our own, and above all, very rich in aqueousvapor. This is a fact of the highest importance because from it we canrightly affirm with much probability that to water and to no otherliquid is due the seas of Mars and its polar snows. When this conclusionis assured beyond all doubt another one may be derived from it of notless importance--that the temperature of the Arean climatenotwithstanding the greater distance of that planet from the sun, is ofthe same order as the temperature of the terrestrial one. Because, if itwere true, as has been supposed by some investigators, that thetemperature of Mars was on the average very low (from 50 degrees to 60degrees below zero), it would not be possible for water vapor to be animportant element in the atmosphere of that planet nor could Water be animportant factor in its physical changes, but would give place tocarbonic acid, or to some other liquid whose freezing point was muchlower.
The elements of the meteorology of Mars seem, then, to have a closeanalogy to those of the earth. But there are not lacking, as might beexpected, causes of dissimilarity. From circumstances of the smallestmoment nature brings forth an infinite variety in its operations. Of thegreatest influence must be different arrangement of the seas and thecontinents upon Mars and upon the earth, regarding which a glance at themap will say more than would be possible in many words. We have alreadyemphasized the fact of the extraordinary periodical flood, which atevery revolution of Mars inundates the northern polar region at themelting of the snow. Let us now add that this inundation is spread outto a great distance by means of a network of canals, perhapsconstituting the principal mechanism (if not the only one) by whichwater (and with it organic life) may be diffused over the arid surfaceof the planet. Because on Mars it rains very rarely, or perhaps even itdoes not rain at all. And this is the proof.
Let us carry ourselves in imagination into celestial space, to a pointso distant from the earth that we may embrace it all at a single glance.He would be greatly in error who had expected to see reproduced thereupon a great scale the image of our continents with their gulfs andislands and with the seas that surround them which are seen upon ourartificial globes. Then without doubt the known forms or parts of themwould be seen to appear under a vaporous veil, but a great part (perhapsone-half) of the surface would be rendered invisible by the immensefields of cloud, continually varying in density, in form, and in extent.Such a hindrance, most frequent and continuous in the polar regions,would still impede nearly half the time the view of the temperate zones,distributing itself in capricious and ever varying configurations. Theseas of the torrid zone would be seen to be arranged in long parallellayers, corresponding to the zone of the equatorial and tropical calms.For an observer placed upon the moon the study of our geography wouldnot be so simple an undertaking as one might at first imagine.
There is nothing of this sort in Mars. In every climate and under everyzone its atmosphere is nearly perpetually clear and sufficientlytransparent to permit one to recognize at any moment whatever thecontours of the seas and continents, and, more than that, even the minorconfigurations. Not indeed that vapors of a certain degree of opacityare lacking, but they offer very little impediment to the study of thetopography of the planet. Here and there we see appear from time to timea few whitish spots, changing their position and their form, rarelyextending over a very wide area. They frequent by preference a fewregions, such as the islands of the Mare Australe, and on the continentsthe regions designated on the map with the names of Elysium and Tempe.Their brilliancy generally diminishes and disappears at the meridianhour of the place, and is re-enforced in the morning and evening withvery marked variations. It is possible that they may be layers of cloudsbecause the upper portions of terrestrial clouds where they areilluminated by the sun appear white. But various observations lead us tothink that we are dealing rather with a thin veil of fog instead of atrue nimbus cloud, carrying storms and rain. Indeed, it may be merely atemporary condensation of vapor under the form of dew or hoar frost.
Accordingly, as far as we may be permitted to argue from the observedfacts, the climate of Mars must resemble that of a clear day upon a highmountain. By day a very strong solar radiation, hardly mitigated at allby mist or vapor; by night a copious radiation from the soil towardcelestial space, and because of that a very marked refrigeration. Hencea climate of extremes, and great changes of temperature from day tonight, and from one season to another. And as on the earth at altitudesof 5,000 and 6,000 meters (17,000 to 20,000 feet) the vapor of theatmosphere is condensed only into the solid form, producing thosewhitish masses of suspended crystals which we call cirrus clouds, so inthe atmosphere of Mars it would be rarely possible (or would even beimpossible) to find collections of cloud capable of producing rain ofany consequence. The variation of the temperature from one season toanother would be notably increased by their long duration, and thus wecan understand the great freezing and melting of the snow which isrenewed in turn at the poles at each complete revolution of the planetaround the sun.
As our chart demonstrates, in its general topography Mars does notpresent any analogy with the earth. A third of its surface is occupiedby the great Mare Australe, which is strewn with many islands, and thecontinents are cut up by gulfs, and ramifications of various forms. Tothe general water system belongs an entire series of small internalseas, of which the Hadriacum and the Tyrrhenum communicate with it bywide mouths, whilst the Cimmerium, the Sirenum, and the Solis Lacus areconnected with it only by means of narrow canals. We shall notice inthe first four a parallel arrangement, which certainly is notaccidental, as also not without reason is the corresponding position ofthe peninsulas of Ausonia, Hesperia, and Atlantis. The color of the seasof Mars is generally brown, mixed with gray, but not always of equalintensity in all places, nor is it the same in the same place at alltimes. From an absolute black it may descend to a light-gray or to anash color. Such a diversity of colors may have its origin in variouscauses, and is not without analogy also upon the earth, where it isnoted that the seas of the warm zone are usually much darker than thosenearer the pole. The water of the Baltic, for example, has a light,muddy color that is not observed in the Mediterranean. And thus in theseas of Mars we see the color become darker when the sun approachestheir zenith, and summer begins to rule in that region.
All of the remainder of the planet, as far as the north pole is occupiedby the mass of the continents, in which, save in a few areas ofrelatively small extent, an orange color predominates, which sometimesreaches a dark red tint, and in others descends to yellow and white. Thevariety in this coloring is in part of meteorological origin, in part itmay depend on the diverse nature of the soil, but upon its real causeit is not as yet possible to frame any very well grounded hypothesis.Nevertheless, the cause of this predominance of the red and yellow tintsupon the surface of ancient Pyrois is well known.[A] Some have thoughtto attribute this coloring to the atmosphere of Mars, through which thesurface of the planet might be seen colored, as any terrestrial objectbecomes red when seen through red glass. But many facts are opposed tothis idea, among others that the polar snows appear always of the purestwhite, although the rays of light derived from them traverse twice theatmosphere of Mars under great obliquity. We must then conclude that theArean continents appear red and yellow because they are so in fact.
Besides these dark and light regions, which we have described as seasand continents, and of whose nature there is at present scarcely leftany room for doubt, some others exist, truly of small extent, of anamphibious nature, which sometimes appear yellowish like the continents,and are sometimes clothed in brown (even black in certain cases), andassume the appearance of seas, whilst in other cases their color isintermediate in tint, and leaves us in doubt to which class of regionsthey may belong. Thus all the islands scattered through the MareAustrale and the Mare Erythr?um belong to this category; so, too, thelong peninsula called Deucalionis Regio and Pyrrhae Regio, and in thevicinity of the Mare Acidalium the regions designated by the name
s ofBaltia and Nerigos. The most natural idea, and the one to which weshould be led by analogy, is to suppose these regions to represent hugeswamps, in which the variation in depth of the water produces thediversity of colors. Yellow would predominate in those parts where thedepth of the liquid layer was reduced to little or nothing, and brown,more or less dark, in those places where the water was sufficiently deepto absorb more light and to render the bottom more or less invisible.That the water of the sea, or any other deep and transparent water, seenfrom above, appears more dark the greater the depth of the liquidstratum, and that the land in comparison with it appears bright underthe solar illumination, is known and confirmed by certain physicalreasons. The traveler in the Alps often has occasion to convince himselfof it, seeing from the summits the deep lakes with which the region isstrewn extending under his feet as black as ink, whilst in contrast withthem even the blackest rocks illumined by the sunlight appearedbrilliant.[B]
Not without reason, then, have we hitherto attributed to the dark spotsof Mars the part of seas, and that of continents to the reddish areaswhich occupy nearly two-thirds of all the planet, and we shall findlater other reasons which confirm this method of reasoning. Thecontinents form in the northern hemisphere a nearly continuous mass, theonly important exception being the great lake called the Mare Acidalium,of which the extent may vary according to the time, and which isconnected in some way with the inundations which we have said wereproduced by the melting of the snow surrounding the north pole. To thesystem of the Mare Acidalium undoubtedly belong the temporary lakecalled Lacus Hyperboreus and the Lacus Niliacus. This last is ordinarilyseparated from the Mare Acidalium by means of an isthmus or regular dam,of which the continuity was only seen to be broken once for a short timein 1888. Other smaller dark spots are found here and there in thecontinental area which we may designate as lakes, but they are certainlynot permanent lakes like ours, but are variable in appearance and sizeaccording to the seasons, to the point of wholly disappearing undercertain circumstances. Ismenius Lacus, Lunae Lacus, Trivium Charontis,and Propontis are the most conspicuous and durable ones. There are alsosmaller ones, such as Lacus Moeris and Fons Juventae, which at theirmaximum size do not exceed 100 to 150 kilometers (60 to 90 miles) indiameter, and are among the most difficult objects upon the planet.
All the vast extent of the continents is furrowed upon every side by anetwork of numerous lines or fine stripes of a more or less pronounceddark color, whose aspect is very variable. These traverse the planet forlong distances in regular lines that do not at all resemble the windingcourses of our streams. Some of the shorter ones do not reach 500kilometers (300 miles), others, on the other hand, extend for manythousands, occupying a quarter or sometimes even a third of acircumference of the planet. Some of these are very easy to see,especially that one which is near the extreme left-hand limit of our mapand is designated by the name of Nilosyrtis. Others in turn areextremely difficult, and resemble the finest thread of spider's webdrawn across the disk. They are subject also to great variations intheir breadth, which may reach 200 or even 300 kilometers (120 to 180miles) for the Nilosyrtis, whilst some are scarcely 30 kilometers (18miles) broad.
These lines or stripes are the famous canals of Mars, of which so muchhas been said. As far as we have been able to observe them hitherto,they are certainly fixed configurations upon the planet. The Nilosyrtishas been seen in that place for nearly one hundred years, and some ofthe others for at least thirty years. Their length and arrangement areconstant, or vary only between very narrow limits. Each of them alwaysbegins and ends between the same regions. But their appearance and theirdegree of visibility vary greatly, for all of them, from one oppositionto another, and even from one week to another, and these variations donot take place simultaneously and according to the same laws for all,but in most cases happen apparently capriciously, or at least accordingto laws not sufficiently simple for us to be able to unravel. Often oneor more become indistinct, or even wholly invisible, whilst others intheir vicinity increase to the point of becoming conspicuous even intelescopes of moderate power. The first of our maps shows all those thathave been seen in a long series of observations. This does not at allcorrespond to the appearance of Mars at any given period, becausegenerally only a few are visible at once.[C]
Every canal (for now we shall so call them) opens at its ends eitherinto a sea, or into a lake, or into another canal, or else into theintersection of several other canals. None of them have yet been seencut off in the middle of the continent, remaining without beginning orwithout end. This fact is of the highest importance. The canals mayintersect among themselves at all possible angles, but by preferencethey converge toward the small spots to which we have given the name oflakes. For example, seven are seen to converge in Lacus Phoenicis,eight in Trivium Charontis, six in Lunae Lacus, and six in IsmeniusLacus.
The normal appearance of a canal is that of a nearly uniform stripe,black, or at least of a dark color, similar to that of the seas, inwhich the regularity of its general course does not exclude smallvariations in its breadth and small sinuosities in its two sides. Oftenit happens that such a dark line opening out upon the sea is enlargedinto the form of a trumpet, forming a huge bay, similar to the estuariesof certain terrestrial streams. The Margaritifer Sinus, the AoniusSinus, the Aurorae Sinus, and the two horns of the Sab?us Sinus are thusformed, at the mouths of one or more canals, opening into the MareErythraeum or into the Mare Australe. The largest example of such a gulfis the Syrtis Major, formed by the vast mouth of the Nilosyrtis, socalled. This gulf is not less than 1,800 kilometers (1,100 miles) inbreadth, and attains nearly the same depth in a longitudinal direction.Its surface is little less than that of the Bay of Bengal. In this casewe see clearly the dark surface of the sea continued without apparentinterruption into that canal. Inasmuch as the surfaces called seas aretruly a liquid expanse, we cannot doubt that the canals are a simpleprolongation of them, crossing the yellow areas or continents.
Of the remainder, that the lines called canals are truly great furrowsor depressions in the surface of the planet, destined for the passage ofthe liquid mass and constituting for it a true hydrographic system, isdemonstrated by the phenomena which are observed during the melting ofthe northern snows. We have already remarked that at the time of meltingthey appear surrounded by a dark zone, forming a species of temporarysea. At that time the canals of the surrounding region become blackerand wider, increasing to the point of converting at a certain time allof the yellow region comprised between the edge of the snow and theparallel of 60 degrees north latitude into numerous islands of smallextent. Such a state of things does not cease until the snow, reduced toits minimum area, ceases to melt. Then the breadth of the canalsdiminishes, the temporary sea disappears, and the yellow region againreturns to its former area. The different phases of these vast phenomenaare renewed at each return of the seasons, and we were able to observethem in all their particulars very easily during the oppositions of1882, 1884, and 1886, when the planet presented its northern pole toterrestrial spectators. The most natural and the most simpleinterpretation is that to which we have referred, of a great inundationproduced by the melting of the snows; it is entirely logical and issustained by evident analogy with terrestrial phenomena. We conclude,therefore, that the canals are such in fact and not only in name. Thenetwork formed by these was probably determined in its origin in thegeological state of the planet, and has come to be slowly elaborated inthe course of centuries. It is not necessary to suppose them the work ofintelligent beings, and, notwithstanding the almost geometricalappearance of all of their system, we are now inclined to believe themto be produced by the evolution of the planet, just as on the earth wehave the English Channel and the channel of Mozambique.
It would be a problem not less curious than complicated and difficult tostudy the system of this immense stream of water, upon which perhapsdepends principally the organic life upon the planet, if organic life isfound there. The variations of their appearance demonstrated
that thissystem is not constant. When they become displaced or their outlinesbecome doubtful and ill defined, it is fair to suppose that the water isgetting low or is even entirely dried up. Then, in place of the canalsthere remains either nothing or at most stripes of yellowish colordiffering little from the surrounding background. Sometimes they take ona nebulous appearance, for which at present it is not possible to assigna reason. At other times true enlargements are produced, expanding to100, 200 or more kilometers (60 to 120 miles) in breadth, and thissometimes happens for canals very far from the north pole, according tolaws which are unknown. This occurred in Hydaspes in 1864, in Simois in1879, in Ackeron in 1884, and in Triton in 1888. The diligent and minutestudy of the transformations of each canal may lead later to a knowledgeof the causes of these effects.
But the most surprising phenomenon pertaining to the canals of Mars istheir germination, which seems to occur principally in the months whichprecede and in those which follow the great northern inundation--atabout the times of the equinoxes. In consequence of a rapid process,which certainly lasts at most a few days, or even perhaps, only a fewhours, and of which it has not yet been possible to determine theparticulars with certainty, a given canal changes its appearance and isfound transformed through all its length into two lines or uniformstripes more or less parallel to one another, and which run straight andequal with the exact geometrical precision of the two rails of arailroad. But this exact course is the only point of resemblance withthe rails, because in dimensions there is no comparison possible, as itis easy to imagine. These two lines follow very nearly the direction ofthe original canal and end in the place where it ended. One of these isoften superposed as exactly as possible upon the former line, the otherbeing drawn anew; but in this case the original line loses all the smallirregularities and curvature that it may have originally possessed. Butit also happens that both the lines may occupy opposite sides of the'former canal and be located upon entirely new ground. The distancebetween the two lines differs in different germinations and varies from600 kilometers (360 miles) and more down to the smallest limit at whichtwo lines may appear separated in large visual telescopes--less than atintervals of 50 kilometers (30 miles). The breadth of the stripesthemselves may range from the limit of visibility, which we may supposeto be 30 kilometers (18 miles), up to more than 100 kilometers (60miles). The color of the two lines varies from black to a light red,which can hardly be distinguished from the general yellow background ofthe continental surface. The space between is for the most part yellow,but in many cases appears whitish. The gemination is not necessarilyconfined only to the canals, but tends to be produced also in thelakes. Often one of these is seen transformed into two short, broad,dark lines parallel to one another and traversed by a yellow line. Inthese cases the gemination is naturally short and does not exceed thelimits of the original lake.
The gemination is not shown by all at the same time, but when the seasonis at hand it begins to be produced here and there, in an isolated,irregular manner, or at least without any easily recognizable order. Inmany canals (such as the Nilosyrtis, for example), the gemination islacking entirely, or is scarcely visible. After having lasted for somemonths, the markings fade out gradually and disappear until anotherseason equally favorable for their formation. Thus it happens that incertain other seasons (especially near the southern solstice of theplanet) few are seen, or even none at all. In different oppositions thegemination of the same canal may present different appearances as towidth, intensity, and arrangement of the two stripes; also in some casesthe direction of the lines may vary, although by the smallest quantity,but still deviating by a small amount from the canal with which they aredirectly associated. From this important fact it is immediatelyunderstood that the gemination cannot be a fixed formation upon thesurface of Mars and of a geographical character like the canals. Thesecond of our maps will give an approximate idea of the appearance whichthese singular formations present. It contains all the geminationsobserved since 1882 up to the present time. In examining it it isnecessary to bear in mind that not all of these appearances weresimultaneous, and consequently that the map does not represent thecondition of Mars at any given period; it is only a sort oftopographical register of the observations made of this phenomenon atdifferent times.[D]
The observation of the gemination is one of the greatest difficulty, andcan only be made by an eye well practiced in such work, added to atelescope of accurate construction and of great power. This explains whyit is that it was not seen before 1882. In the ten years that havetranspired since that time, it has been seen and described at eight orten observatories. Nevertheless, some still deny that these phenomenaare real, and tax with illusion (or even imposture) those who declarethat they have observed it.
Their singular aspect, and their being drawn with absolute geometricalprecision, as if they were the work of rule or compass, has led some tosee in them the work of intelligent beings, inhabitants of the planet. Iam very careful not to combat this supposition, which includes nothingimpossible. (Io mi guarder? bene dal combattere questa supposizione, laquale nulla include d'impossibile.) But it will be noticed that in anycase the gemination cannot be a work of permanent character, it beingcertain that in a given instance it may change its appearance anddimensions from one season to another. If we should assume such a work,a certain variability would not be excluded from it; for example,extensive agricultural labor and irrigation upon a large scale. Let usadd, further, that the intervention of intelligent beings might explainthe geometrical appearance of the gemination, but it is not at allnecessary for such a purpose. The geometry of nature is manifested inmany other facts from which are excluded the idea of any artificiallabor whatever. The perfect spheroids of the heavenly bodies and thering of Saturn were not constructed in a turning lathe, and not withcompasses has Iris described within the clouds her beautiful and regulararch. And what shall we say of the infinite variety of those exquisiteand regular polyhedrons in which the world of crystals is so rich? Inthe organic world, also, is not that geometry most wonderful whichpresides over the distribution of the foliage upon certain plants, whichorders the nearly symmetrical, star-like figures of the flowers of thefield, as well as of the sea, and which produces in the shell such anexquisite conical spiral that excels the most beautiful masterpieces ofGothic architecture? In all these objects the geometrical form is thesimple and necessary consequence of the principles and laws which governthe physical and physiological world. That these principles and theselaws are but an indication of a higher intelligent Power we may admit,but this has nothing to do with the present argument.
Having regard, then, for the principle that in the explanation ofnatural phenomena it is universally agreed to begin with the simplestsuppositions, the first hypotheses of the nature and cause of thegeminations have for the most part put in operation only the laws ofinorganic nature. Thus, the gemination is supposed to be due either tothe effects of light in the atmosphere of Mars, or to optical illusionsproduced by vapors in various manners, or to glacial phenomena of aperpetual winter, to which it is known all the planets will becondemned, or to double cracks in its surface, or to single cracks ofwhich the images are doubled by the effect of smoke issuing in longlines and blown laterally by the wind. The examination of theseingenious suppositions leads us to conclude that none of them seem tocorrespond entirely with the observed facts, either in whole or in part.Some of these hypotheses would not have been proposed had their authorsbeen able to examine the geminations with their own eyes. Since some ofthese may ask me directly, "Can you suggest anything better?" I mustreply candidly, "No."
It would be far more easy if we were willing to introduce the forcespertaining to organic nature. Here the field of plausible supposition isimmense, being capable of making an infinite number of combinationscapable of satisfying the appearances even with the smallest andsimplest means. Changes of vegetation over a vast area, and theproduction of animals, also very small, but in enormous multitudes, maywell be rendered vi
sible at such a distance. An observer placed in themoon would be able to see such an appearance at the times in whichagricultural operations are carried out upon one vast plain--theseed-time and the gathering of the harvest. In such a manner also wouldthe flowers of the plants of the great steppes of Europe and Asia berendered visible at the distance of Mars--by a variety of coloring. Asimilar system of operations produced in that planet may thus certainlybe rendered visible to us. But how difficult for the Lunarians and theAreans to be able to imagine the true causes of such changes ofappearance without having first at least some superficial knowledge ofterrestrial nature! So also for us, who know so little of the physicalstate of Mars, and nothing of its organic world, the great liberty ofpossible supposition renders arbitrary all explanations of this sort andconstitutes the gravest obstacle to the acquisition of well-foundednotions. All that we may hope is that with time the uncertainty of theproblem will gradually diminish, demonstrating if not what thegeminations are, at least what they cannot be. We may also confide alittle in what Galileo called "the courtesy of nature," thanks to whicha ray of light from an unexpected source will sometimes illuminate aninvestigation at first believed inaccessible to our speculations, and ofwhich we have a beautiful example in celestial chemistry. Let ustherefore hope and study.
FOOTNOTES:
[Footnote A: Pyrois I take to be some terrestrial region, although Ihave not been able to find any translation of the name.--Translator.]
[Footnote B: This observation of the dark color which deep waterexhibits when seen from above is found already noted by the first authorof antique memory, for in the Iliad (verses 770-771 of Book V) it isdescribed how "the sentinel from the high sentry box extends his glanceover the wine-colored sea, [Greek: _oinopa phonton_]." In the version ofMonti the adjective indicating the color is lost.]
[Footnote C: In a footnote the author refers to a drawing of Mars madeby himself, September 15, 1892, and says, ... "At the top of the diskthe Mare Erythraeum and the Mare Australe appear divided by a greatcurved peninsula, shaped like a sickle, producing an unusual appearancein the area called Deucalionis Regio, which was prolonged that year soas to reach the islands of Noachis and Argyre. This region forms withthem a continuous whole, but with faint traces of separation occurringhere and there in a length of nearly 6,000 kilometers (4,000 miles). Itscolor, much less brilliant than that of the continents, was a mixture oftheir yellow with the brownish gray of the neighboring seas." Theinteresting feature of this note is the remark that it was an unusualappearance, the region referred to being that in which the centralbranch of the fork of the Y appeared. Since no such branch wasconspicuously visible this year, it would therefore seem from the abovethat it was the opposition of 1892 that was peculiar, and not thepresent one.--Translator.]
[Footnote D: This map may be found also in La Plan?te Mars, byFlammarion, page 44.--Translator.]
Certainty of a Future Life in Mars Page 8
