Science in Arcady

In very cold countries, on the other hand, though the conditions are severe, the struggle for existence is not really so hard, because, in one word, there are fewer competitors. The field is less occupied; life is less rich, less varied, less self-strangling. And therefore specialisation hasn't gone nearly so far in cold latitudes or altitudes. Lower and simpler types everywhere occupy the soil; mosses, matted flowers, small beetles, dwarf butterflies. Nature is less luxuriant, yet in some ways more beautiful. As we rise on the mountains the forest trees disappear, and with them the forest beasts, from bears to squirrels; a low, wind-swept vegetation succeeds, very poor in species, and stunted in growth, but making a floor of rich flowers almost unknown elsewhere. The humble butterflies and beetles of the chillier elevation produce in the result more beautiful bloom than the highly developed honey-seekers of the richer and warmer lowlands. Luxuriance is atoned for by a Turkey carpet of floral magnificence.

How, then, has the world at large fallen into the pardonable error of believing tropical nature to be so rich in colouring, and circumpolar nature to be so dingy and unlovable? Simply thus, I believe. The tropics embrace the largest land areas in the world, and are richer by a thousand times in species of plants and animals than all the rest of the earth in a lump put together. That richness necessarily results from the fierceness of the competition. Now among this enormous mass of tropical plants it naturally happens that some have finer flowers than any temperate species; while as to the animals and birds, they are undoubtedly, on the whole, both larger and handsomer than the fauna of colder climates. But in the general aspect of tropical nature an occasional bright flower or brilliant parrot counts for very little among the mass of lush green which surrounds and conceals it. On the other hand, in our museums and conservatories we sedulously pick out the rarest and most beautiful of these rare and beautiful species, and we isolate them completely from their natural surroundings. The consequence is that the untravelled mind regards the tropics mentally as a sort of perpetual replica of the hot-houses at Kew, superimposed on the best of Mr. Bull's orchid shows. As a matter of fact, people who know the hot world well can tell you that the average tropical woodland is much more like the dark shade of Box Hill or the deepest glades of the Black Forest. For really fine floral display in the mass, all at once, you must go, not to Ceylon, Sumatra, Jamaica, but to the far north of Canada, the Bernese Oberland, the moors of Inverness-shire, the North Cape of Norway. Flowers are loveliest where the climate is coldest; forests are greenest, most luxuriant, least blossoming, where the conditions of life are richest, warmest, fiercest. In one word, High Life is always poor but beautiful.

EIGHT-LEGGED FRIENDS

A singular opportunity was afforded me last summer for making myself thoroughly at home with the habits and manners of the common English geometrical spider. By the pure chance of circumstance, two ladies of that intelligent and interesting species were kind enough to select for their temporary residence a large pane of glass just outside my drawing-room window. Now, it so happened that this particular pane was constructed not to open, being, in fact, part of a big bow-window, the alternate sashes of which were alone intended for ventilation. Hence it came to pass that by diligent care I was enabled to preserve my two eight-legged acquaintances from the devouring broom of the British housemaid, and to keep them constantly under observation at all times and seasons during a whole summer. Of course this result was only obtained by a distinct exercise of despotic authority, for I know those poor spiders were a constant eyesore in Ellen's sight—the housemaid of the moment bore the name of Ellen—but I persisted in my prohibition of any forcible ejectment, and I carried my point in the end in the very teeth of that constituted domestic authority. So successful was I, indeed, that when at last we flitted southwards ourselves with the swallows on our annual migration to the Mediterranean shores, we left Lucy and Eliza—those were the names we had given them—in undisturbed possession of their prescriptive rights in the drawing-room windows. This year they are gone, and our home is left spiderless.

They were curious and uninviting pets, I'm bound to admit, those great juicy-looking creatures. Nobody could say that any form of spider is precisely what our Italian friends prettily describe in their liquid way as simpatico. At times, indeed, the conduct of Lucy and Eliza was so peculiarly horrible and blood-curdling in its atrocity, that even I, their best friend, who had so often interceded for their lives and saved them from the devastating duster of the aggressive housemaid—even I myself, I say, more than once debated in my own mind whether I was justified in letting them go on any longer in their career of crime unchecked, or whether I ought not rather to rush out at once, avenging rag in hand, and sweep them away at one fell swoop from the surface of a world they disgraced with their unbridled wickedness. Eliza, in particular, I'm constrained to allow, was a perfect monster of vice—a sort of undeveloped arachnid Borgia, quick to slay and relentless in pursuit; a mass of eight-legged sins, stained with the colourless gore of ten thousand struggling victims, and absolutely without a single redeeming point in her hateful character. And yet, whenever any more than usually horrible massacre of some pretty and innocent fly almost moved me in my righteous wrath to rush out into the garden in hot haste and put an end at once to the cruel wretch's existence with a judicial antimacassar, a number of moral scruples, such as could only be adequately resolved by the editor of the Spectator, always occurred spontaneously to my mind and conscience just in time to ensure that wicked Eliza a fresh spell of life in which to continue unabashed her atrocious behaviour.

Has man, I asked myself at such moments, mere human man, any right to set himself up in the place of earthly providence, as so much better and more moral than insentient nature? If the spider cruelly devours living flies and intelligent or highly sensitive bees, we must at least remember that she has no choice in the matter, and that, as the poet justly remarks, ''tis her nature to.' But then, on the other hand, it might be plausibly argued that 'tis our nature equally to kill the creature that we see so hatefully fulfilling the law of its own cruel being. And yet again it might be pleaded by any able counsel who undertook the defence of Lucy or Eliza on her trial for her life against her human accusers, that she was impelled to all these evil deeds by maternal affection, one of the noblest and most unselfish of animal instincts. Moreover, if the spider didn't prey, it would obviously die; and it seems rather hard on any creature to condemn it to death for no better reason than because it happens to have been born a member of its own kind, and not of any other and less morally objectionable species. Jedburgh justice o£ that sort rather savours of the method pursued by the famous countryman who was found cutting a harmless amphibian into a hundred pieces with his murderous spade, and saying spitefully as he did so, at every particularly savage cut: 'I'll larn ye to be a twoad, I will; I'll larn ye to be a twoad!'

Nevertheless, in spite of all this my vaunted philosophy, I will frankly confess that more than once Eliza and Lucy sorely tried my patience, and that I was often a good deal better than half-minded in my soul to rush out in a feverish fit of moral indignation and put an end to their ghastly career of crime without waiting to hear what they had to say in their own favour, showing cause why sentence of death should not be executed upon them. And I would have done it, I believe, had it not been for that peculiar arrangement of the drawing-room windows, which made it impossible to get at the culprits direct, without going out into the garden and round the house; which, of course, is a severe strain in wet or windy weather to put upon anybody's moral enthusiasm. In the end, therefore, I always gave the evil-doers the benefit of the doubt; and I only mention my ethical scruples in the matter here lest scoffers should say, when they come to read what manner of things Lucy and Eliza did: 'Oh yes, that's just like those scientific folks; they're always so cold-blooded. He could stand by and see these poor helpless flies tortured slowly to death, without a chance for their lives, and never put out a helping hand to save them!' Well, I would only ask you one question, my sapient friend, who talk like that: Has it ever occurred to you that, if you kill one spider, you merely make room in the overflowing economy of nature for another to pick up a dishonest livelihood? Have you ever reflected that the prime blame of spiderhood rests with Nature herself (if we may venture to personify that impersonal entity); and that she has provided such a constant supply or relay of spiders as will amply suffice to fill up all the possible vacancies that can ever occur in insect-eating circles? Unless you have considered all these points carefully, and have an answer to give about them, you are not in a position to pronounce upon the subject, and you had better be referred for six months longer, as the medical examiners gracefully put it, to your ethical, psychological, and biological studies. The great point about the position in which Eliza and Lucy had placed themselves was simply this. They stood full against the light, so that we could see right through their translucent bodies, which were almost liquid to look upon, and beautifully dappled with dark spots on a grey ground in a very pretty and effective pattern. So favourable was the opportunity for observation, indeed, that we could clearly make out with the naked eye even the joints of their legs, the hairs on their tarsi—excuse the phrase—and the very shape of their cruel tigerlike claws, as they rushed forth upon their prey in a sort of carnivorous frenzy. At all hours of the day we could notice exactly what they were doing or suffering; and so familiar did we become with them individually and personally, that before the end of the season we recognized in detail all the differences of their characters almost as one might do with cats or dogs, and spoke of them by their Christian names like old and well-known acquaintances.

As the webs which Lucy and Eliza spun were several times broken or mutilated during the year, either by accident or the gardener, we had plenty of chances for seeing how they proceeded in making them. The lines were in both cases stretched between a white rose-bush that climbed up one side of the window, and a purple clematis that occupied and draped the opposite mullion. But Lucy and Eliza didn't live in the webs—those were only their snares or traps for prey; each of them had in addition a private home or apartment of her own under shelter of a rose-leaf at some distance from the treacherous geometrical structure. The house itself consisted merely of a silken cell, built out from the rose-leaf, and connected with the snare by a single stout cord of very solid construction. On this cord the spider kept one foot—I had almost said one hand—constantly fixed. She poised it lightly by her claws, and whenever an insect got entangled in the web, a subtle electric message, so to speak, seemed to run along the line to the ever-watchful carnivore. In one short second Lucy or Eliza, as the case might be, had darted out upon her quarry, and was tackling it might main, according to the particular way its size and strength rendered then and there advisable. The method of procedure, which I shall describe more fully by-and-by, differed considerably from case to case, as these very large and strong spiders have sometimes to deal with mere tiny midges, and sometimes with extremely big and dangerous creatures, like bumble-bees, wasps, and even hornets.

In building their webs, as in many other small points, Lucy and Eliza showed from the first no inconsiderable personal differences. Lucy began hers by spinning a long line from her spinnerets, and letting the wind carry it wherever it would; while Eliza, more architectural in character, preferred to take her lines personally from point to point, and see herself to their proper fastening. In either case, however, the first thing done was to stretch some eight or ten stout threads from place to place on the outside of the future web, to act as points d'appuy for the remainder of the structure. To these outer threads, which the spiders strengthened so as to bear a considerable strain by doubling and trebling them, other thinner single threads were then carried radially at irregular distances, like the spokes of a wheel, from a point in the centre, where they were all made fast and connected together. As soon as this radiating framework or scaffolding was finished, like the woof on a loom, the industrious craftswoman started at the middle, and began the task of putting in the cross-pieces or weft which were to complete and bind together the circular pattern. These she wove round and round in a continuous spiral, setting out at the centre, and keeping on in ever-widening circlets, till she arrived at last at the exterior or foundation threads. How she fastened these cross-pieces to the ray-lines I could never quite make out, though I often followed the work closely from inside through the pane of glass with a platyscopic lens; for, strange to say, the spiders were not in the least disturbed by being watched at their work, and never took the slightest notice of anything that went on at the other side of the window. My impression is, however, that she gummed them together, letting them harden into one as they dried; for the thread itself is always semi-liquid when first exuded.

The cross-pieces, we observed from the very beginning, were invariably covered by little sparkling drops of something wet and beadlike, which at first in our ignorance we took for dew; for until I began systematically observing Lucy and Eliza, I will frankly confess I had never paid any particular attention to the spider-kind with the solitary exception of my old winter friends, the trap-door spiders of the Mediterranean shores. But, after a little experience, we soon found out that these pearly drops on the web were not dew at all, but a sticky substance, akin, to that of the web, secreted by the animals themselves from their own bodies. We also quickly discovered, coming to the observation as we did with minds unbiased by previous knowledge, that the viscid liquid in question was of the utmost importance to the spiders in securing their prey, and that unfortunate insects were not merely entangled but likewise gummed down or glued by it, like birds in bird-lime or flies in treacle. So necessary is the sticky stuff, indeed, to the success of the trap, that Lucy and Eliza used to renew the entire set of cross-pieces in the web every morning, and thus ensure from day to day a perfectly fresh supply of viscid fluid; but, so far as I could see, they only renewed the rays and the foundation-threads under stress of necessity, when the snare had been so greatly injured by large insects struggling in it, or by the wind or the gardener, as to render repairs absolutely unavoidable. The whole structure, when complete, is so beautiful and wonderful a sight, with its geometrical regularity and its beaded drops, that if it were produced by a rare creature from Madagascar or the Cape, in the insect-house at the Zoo, all the world, I'm convinced, would rush to look at it as a nine-days' wonder. But since it's only the trap of the common English garden spider, why, we all pass it by without deigning even to glance at it.

At night my eight-legged friends slept always in their own homes or nests under shelter of the rose-leaves. But during the day they alternated between the nest and the centre of the web, which last seemed to serve them as a convenient station where they waited for their prey, standing head downward with legs wide spread on the rays, on the look-out for incidents. Whether at the centre or in the nest, however, they kept their feet constantly on the watch for any disturbance on the webs; and the instant any unhappy little fly got entangled in their meshes, the ever-watchful spider was out like a flash of lightning, and down at once in full force upon that incautious intruder. I was convinced after many observations that it is by touch alone the spider recognizes the presence of prey in its web, and that it hardly derives any indications worth speaking of from its numerous little eyes, at least as regards the arrival of booty. If a very big insect has got into the web, then a relatively large volume of disturbance is propagated along the telegraphic wire that runs from the snare to the house, or from the circumference to the centre; if a small one, then a slight disturbance; and the spider rushes out accordingly, either with an air of caution or of ferocious triumph.

Supposing the booty in hand was a tiny fly, then Lucy or Eliza would jump upon it at once with that strange access of apparently personal animosity with seems in some mysterious way a characteristic of all hunting carnivorous animals. She would then carelessly wind a thread or two about it, in a perfunctory way, bury her jaws in its body, and in less than half a minute suck out its juices to the last drop, leaving the empty shell unhurt, like a dry skeleton or the slough of a dragon-fly larva. But when wasps or other large and dangerous insects got entangled in the webs, the hunters proceeded with far greater caution. Lucy, indeed, who was a decided coward, would stand and look anxiously at the doubtful intruder for several seconds, feeling the web with her claws, and running up and down in the most undecided manner, as if in doubt whether or not to tackle the uncertain customer. But Eliza, whose spirits always rose like Nelson's before the face of danger, and whose motto seemed to be 'De l'audace, de l'audace, et toujours de l'audace,' would rush at the huge foe in a perfect transport of wild fury, and go to work at once to enclose him in her toils of triple silken cables. I always fancied, indeed, that Eliza was in a thoroughly housewifely tantrum at seeing her nice new web so ruthlessly torn and tattered by the unwelcome visitor, and that she said to herself in her own language: 'Oh well, then, if you will have it, you shall have it; so here goes for you.' And go for him she did, with most unladylike ferocity. Indeed, Eliza's best friend, I must fain admit, could never have said of her that she was a perfect lady.

The chawing-up of that wasp was a sight to behold. I have no great sympathy with wasps—they have done me so many bad turns in my time that I don't pretend to regard them as deserving of exceptional pity—but I must say Eliza's way of going at them was unduly barbaric. She treated them for all the world as if they were entirely devoid of a nervous system. I wouldn't treat a Saturday Reviewer myself as that spider treated the wasps when once she was sure of them. She went at them with a sort of angry, half-contemptuous dash, kept cautiously out of the way of the protruded sting, began in most business-like fashion at the head, and rolling the wasp round and round with her legs and feelers, swathed him rapidly and effectually, with incredible speed, in a dense network of web poured forth from her spinnerets. In less than half a minute the astonished wasp, accustomed rather to act on the offensive than the defensive, found himself helplessly enclosed in a perfect coil of tangled silk, which confined him from head to sting without the possibility of movement in any direction. The whole time this had been going on the victim, struggling and writhing, had been pushing out its sting and doing the very best it knew to deal the wily Eliza a poisoned death-blow. But Eliza, taught by ancestral experience, kept carefully out of the way; and the wasp felt itself finally twirled round and round in those powerful hands, and tied about as to its wings by a thousand-fold cable. Sometimes, after the wasp was secured, Eliza even took the trouble to saw off the wings so as to prevent further struggling and consequent damage to the precious web; but more often she merely proceeded to eat it alive without further formality, still avoiding its sting as long as the creature had a kick left in it, but otherwise entirely ignoring its character as a sentient being in the most inhuman fashion. And all the time, till the last drop of his blood was sucked out, the wasp would continue viciously to stick out his deadly sting, which the spider would still avoid with hereditary cunning. It was a horrid sight—a duel à outrance between two equally hateful and poisonous opponents; a living commentary on the appalling but o'er-true words of the poet, that 'Nature is one with rapine, a harm no preacher can heal.' Though these were the occasions when one sometimes felt as if the cup of Eliza's iniquities was really full, and one must pass sentence at last, without respite or reprieve, upon that life-long murderess.

One insect there was, however, before which even Eliza herself, hardened wretch as she seemed, used to cower and shiver; and that was the great black bumble-bee, the largest and most powerful of the British bee-kind. When one of these dangerous monsters, a burly, buzzing bourgeois, got entangled in her web, Eliza, shaking in her shoes (I allow her those shoes by poetical licence) would retire in high dudgeon to her inmost bower, and there would sit and sulk, in visible bad temper, till the clumsy big thing, after many futile efforts, had torn its way by main force out of the coils that surrounded it. Then, the moment the telegraphic communication told her the lines in the web were once more free, Eliza would sally forth again with a smiling face—oh yes, I assure you, we could tell by her look when she was smiling—and would repair afresh with cheerful alacrity the damage done to her snare by the unwelcome visitor. Hummingbird hawk-moths, on the other hand, though so big and quick, she would kill immediately. As for Lucy, craven soul, she had so little sense of proper pride and arachnid honour, that she shrank even from the wasps which Eliza so bravely and unhesitatingly tackled; and more than once we caught her in the very act of cutting them out entire, with the whole piece of web in which they were immeshed, and letting them drop on to the ground beneath, merely as a short way of getting rid of them from her premises. I always rather despised Lucy. She hadn't even the one redeeming virtue of most carnivorous or predatory races—an insensate and almost automatic courage.

I need hardly say, however, that the spider does not kill her prey by a mere fair-and-square bite alone. She has recourse to the art of the Palmers and Brinvilliers. All spiders, as far as known, are provided with poison-fangs in the jaws, which sometimes, as in the tarantula and many other large tropical kinds, well known to me in Jamaica and elsewhere, are sufficiently powerful to produce serious effects upon man himself; while even much smaller spiders, like Eliza and Lucy, have poison enough in their falces, as the jawlike organs are called, to kill a good big insect, such as a wasp or a bumble-bee. These channelled poison-glands, combined with their savage tigerlike claws, make the spiders as a group extremely formidable and dominant creatures, the analogues in their own smaller invertebrate world of the serpents and wolves in the vertebrate creation.

Lucy and Eliza's family relations, I am sorry to say, were not, we found, of a kind to endear them to a critical public already sufficiently scandalized by their general mode of behaviour to their inoffensive neighbours. As mothers, indeed, gossip itself had not a word of blame to whisper against them; but as wives, their conduct was distinctly open to the severest animadversion. The males of the garden spider, as in many other instances, are decidedly smaller than their big round mates; so much so is this the case, indeed, in certain species that they seem almost like parasites of the immensely larger sack-bodied females. Now, just as the worker bees kill off the drones as soon as the queen-bee has been duly fertilized, regarding them as of no further importance or value to the hive, so do the lady-spiders not only kill but eat their husbands as soon as they find they have no further use for them. Nay, if a female spider doesn't care for the looks of a suitor who is pressing himself too much upon her fond attention, her way of expressing her disapprobation of his appearance and manners is to make a murderous spring at him, and, if possible, devour him. Under these painful circumstances the process of courtship is necessarily to some extent a difficult and delicate one, fraught with no small danger to the adventurous swain who has the boldness to commend himself by personal approach to these very fickle and irascible fair ones. It was most curious and exciting, accordingly, to watch the details of the strange courtship, which we could only observe in the case of the cruel Eliza, the rather gentler Lucy having been already mated, apparently, before she took up her quarters in our climbing white rose-bush. One day, however, a timid-looking male spider, with inquiry and doubt in every movement of his tarsi, strolled tentatively up on the neat round web where Eliza was hanging, head downward as usual, all her feet on the thread, on the look-out for house-flies. We knew he was a male at once by his longer and thinner body, and by his natural modesty. He walked gingerly on all eights, like an arachnid Agag, in the direction of the object of his ardent affections, with a most comic uncertainty in every step he took towards her. His claws felt the threads as he moved with anxious care; and it was clear he was ready at a moment's notice to jump away and flee for his life with headlong speed to his native obscurity if Eliza showed the slightest disposition, by gesture or movement, to turn and rend him. Now and again, as he approached, Eliza, half coquettish, moved her feet a short step, and seemed to debate within her own mind in which spirit she should meet his flattering advances—whether to accept him or to eat him. At each such hesitation, the unhappy male, fearing the worst, and sore afraid, would turn on his heel and fly for dear life as fast as eight trembling legs would carry him. Then, after a minute or two, he would evidently come to the conclusion that he had wronged his lady-love, and that her movement was one of true, true love rather than of carnivorous and cannibalistic appetite. At last, as I judged, his constancy was rewarded, though his ominous disappearance very shortly afterwards made me fear for the worst as to his final adventures.

In the end, Eliza laid a large number of eggs in a silken cocoon, in shape a balloon, and secreted, like the web, by her invaluable spinnerets. Indeed, the real reason—I won't say excuse—for the rapacity and Gargantuan appetite of the spider lies, no doubt, in the immense amount of material she has to supply for her daily-renewed webs, her home, and her cocoon, all which have actually to be spun out of the assimilated food-stuffs in her own body; to say nothing of the additional necessity imposed upon her by nature for laying a trifle of six or seven hundred eggs in a single summer. And, to tell the truth, Lucy and Eliza seemed to us to be always eating. No matter at what hour one looked in upon them, they were pretty constantly engaged in devouring some inoffensive fly, or weaving hateful labyrinths of hasty cord round some fiercely-struggling wasp or some unhappy beetle.

We weren't fortunate enough, I regret to say, to see Eliza's eggs hatch out from the cocoon; but in other instances, especially in Southern Europe, I have noticed the little heap of well-covered ova, glued together into a mass, and attached to a branch or twig by stout silken cables. If you open the cocoon when the young spiders are just hatched, they begin to run about in the most lively fashion, and look like a living and moving congeries of little balls or seedlets. The common garden spider lays some seven hundred or more such eggs at a sitting, and out of those seven hundred only two on an average reach maturity and once more propagate their kind. For if only four lived and throve, then clearly, in the next generation, there would be twice as many spiders as in this; and in the generation after that again, four times as many; and then eight times; and so on ad infinitum, until the whole world was just one living and seething mass of common garden spiders.

What keeps them down, then, in the end to their average number? What prevents the development of the whole seven hundred? The simple answer is, continuous starvation. As usual, nature works with cruel lavishness. There are just as many spiders at any given minute as there are insects enough in the world or in their area to feed upon. Every spider lays hundreds of eggs, so as to make up for the average infant mortality by starvation, or by the attacks of ichneumon flies, or by being eaten themselves in the young stage, or by other casualties. And so with all other species. Each produces as many young on the average as will allow for the ordinary infant mortality of their kind, and leave enough over just to replace the parents in the next generation. And that's one of the reasons why it's no use punishing Lucy and Eliza for their misdeeds in this world. Kill them off if you will, and before next week a dozen more like them will dispute with one another the vacant place you have thus created in the balanced economy of that microcosm the garden.

Our observations upon Lucy and Eliza, however, had the effect of making us take an increased interest thenceforth in spiders in general, which till that time we had treated with scant courtesy, and set us about learning something as to the extraordinary variety of life and habit to be found within the range of this single group of arthropods, at first sight so extremely alike in their shapes, their appearance, their morals, and their manners. It's perfectly astonishing, though, when one comes to look into it in detail, how exceedingly diverse spiders are in their mode of life, their structure, and the variety of uses to which they put their one extremely distinctive structural organ, the spinnerets. I will only say here that some spiders use these peculiar glands to form light webs by whose aid, though wingless, they float balloon-wise through the air; that others employ them to line the sides of their underground tunnels, and to make the basis of their marvellously ingenious earthen trap-doors; that yet others have learnt how to adapt these same organs to a subaquatic existence, and to fill cocoons with air, like miniature diving bells; while others, again, have taught themselves to construct webs thick enough to catch and hold even creatures so superior to themselves in the scale of being as humming-birds and sunbirds. This extraordinary variety in the utilization of a single organ teaches once more the same lesson which is impressed upon us elsewhere by so many other forms of organic evolution: whatever enables an animal or plant to gain an advantage over others in the struggle for life, no matter in what way, is sure to survive, and to be turned in time to every conceivable use of which its structure is capable, in the infinite whirligig of ever-varying nature.

MUD

Even a prejudiced observer will readily admit that the most valuable mineral on earth is mud. Diamonds and rubies are just nowhere by comparison. I don't mean weight for weight, of course—mud is 'cheap as dirt,' to buy in small quantities—but aggregate for aggregate. Quite literally, and without hocus-pocus of any sort, the money valuation of the mud in the world must outnumber many thousand times the money valuation of all the other minerals put together. Only we reckon it usually not by the ton, but by the acre, though the acre is worth most where the mud lies deepest. Nay, more, the world's wealth is wholly based on mud. Corn, not gold, is the true standard of value. Without mud there would be no human life, no productions of any kind: for food stuffs of every description are raised on mud; and where no mud exists, or can be made to exist, there, we say, there is desert or sand-waste. Land, without mud, has no economic value. To put it briefly, the only parts of the world that count much for human habitation are the mud deposits of the great rivers, and notably of the Nile, the Euphrates, the Ganges, the Indus, the Irrawaddy, the Hoang Ho, the Yang-tse-Kiang; of the Po, the Rhone, the Danube, the Rhine, the Volga, the Dnieper; of the St. Lawrence, the Mississippi, the Missouri, the Orinoco, the Amazons, the La Plata. A corn-field is just a big mass of mud; and the deeper and purer and freer from stones or other impurities it is the better.

But England, you say, is not a great river-mud field; yet it supports the densest population in the world. True; but England is an exceptional product of modern civilization. She can't feed herself: she is fed from Odessa, Alexandria, Bombay, New York, Montreal, Buenos Ayres—in other words, from the mud fields of the Russian, the Egyptian, the Indian, the American, the Canadian, the Argentine rivers. Orontes, said Juvenal, has flowed into Tiber; Nile, we may say nowadays, with equal truth, has flowed into Thames.

There is nothing to make one realize the importance of mud, indeed, like a journey up Nile when the inundation is just over. You lounge on the deck of your dahabieh, and drink in geography almost without knowing it. The voyage forms a perfect introduction to the study of mudology, and suggests to the observant mind (meaning you and me) the real nature of mud as nothing else on earth that I know of can suggest it. For in Egypt you get your phenomenon isolated, as it were, from all disturbing elements. You have no rainfall to bother you, no local streams, no complex denudation: the Nile does all, and the Nile does everything. On either hand stretches away the bare desert, rising up in grey rocky hills. Down the midst runs the one long line of alluvial soil—in other words, Nile mud—which alone allows cultivation and life in that rainless district. The country bases itself absolutely on mud. The crops are raised on it; the houses and villages are built of it; the land is manured with it; the very air is full of it. The crude brick buildings that dissolve in dust are Nile mud solidified; the red pottery of Assiout is Nile mud baked hard; the village mosques and minarets are Nile mud whitewashed. I have even seen a ship's bulwarks neatly repaired with mud. It pervades the whole land, when wet, as mud undisguised; when dry, as dust-storm.

Egypt, says Herodotus, is a gift of the Nile. A truer or more pregnant word was never spoken. Of course it is just equally true, in a way, that Bengal is a gift of the Ganges, and that Louisiana and Arkansas are gifts of the Mississippi; but with this difference, that in the case of the Nile the dependence is far more obvious, far freer from disturbing or distracting details. For that reason, and also because the Nile is so much more familiar to most English-speaking folk than the American rivers, I choose Egypt first as my type of a regular mud-land. But in order to understand it fully you mustn't stop all your time in Cairo and the Delta; you mustn't view it only from the terrace of Shepheard's Hotel or the rocky platform of the Great Pyramid at Ghizeh: you must push up country early, under Mr. Cook's care, to Luxor and the First Cataract. It is up country that Egypt unrolls itself visibly before your eyes in the very process of making: it is there that the full importance of good, rich black mud first forces itself upon you by undeniable evidence.

For remember that, from a point above Berber to the sea, the dwindling Nile never receives a single tributary, a single drop of fresh water. For more than fifteen hundred miles the ever-lessening river rolls on between bare desert hills and spreads fertility over the deep valley in their midst—just as far as its own mud sheet can cover the barren rocky bottom, and no farther. For the most part the line of demarcation between the grey bare desert and the cultivable plain is as clear and as well-defined as the margin of sea and land: you can stand with one foot on the barren rock and one on the green soil of the tilled and irrigated mud-land. For the water rises up to a certain level, and to that level accordingly it distributes both mud and moisture: above it comes the arid rock, as destitute of life, as dead and bare and lonely as the centre of Sahara. In and out, in waving line, up to the base of the hills, cultivation and greenery follow, with absolute accuracy, the line of highest flood-level; beyond it the hot rock stretches dreary and desolate. Here and there islands of sandstone stand out above the green sea of doura or cotton; here and there a bay of fertility runs away up some lateral valley, following the course of the mud; but one inch above the inundation-mark vegetation and life stop short all at once with absolute abruptness. In Egypt, then, more than anywhere else, one sees with one's own eyes that mud and moisture are the very conditions of mundane fertility.

Beyond Cairo, as one descends seaward, the mud begins to open out fan-wise and form a delta. The narrow mountain ranges no longer hem it in. It has room to expand and spread itself freely over the surrounding country, won by degrees from the Mediterranean. At the mouths the mud pours out into the sea and forms fresh deposits constantly on the bottom, which are gradually silting up still newer lands to seaward. Slow as is the progress of this land-forming action, there can be no doubt that the Nile has the intention of filling up by degrees the whole eastern Mediterranean, and that in process of time—say in no more than a few million years or so, a mere bagatelle to the geologist—with the aid of the Po and some other lesser streams, it will transform the entire basin of the inland sea into a level and cultivable plain, like Bengal or Mesopotamia, themselves (as we shall see) the final result of just such silting action.

It is so very important, for those who wish to see things "as clear as mud," to understand this prime principle of the formation of mud-lands, that I shall make no apology for insisting on it further in some little detail; for when one comes to look the matter plainly in the face, one can see in a minute that almost all the big things in human history have been entirely dependent upon the mud of the great rivers. Thebes and Memphis, Rameses and Amenhotep, based their civilisation absolutely upon the mud of Nile. The bricks of Babylon were moulded of Euphrates mud; the greatness of Nineveh reposed on the silt of the Tigris. Upper India is the Indus; Agra and Delhi are Ganges and Jumna mud; China is the Hoang Ho and the Yang-tse-Kiang; Burmah is the paddy field of the Irrawaddy delta. And so many great plains in either hemisphere consist really of nothing else but mud-banks of almost incredible extent, filling up prehistoric Baltics and Mediterraneans, that a glance at the probable course of future evolution in this respect may help us to understand and to realize more fully the gigantic scale of some past accumulations.

As a preliminary canter I shall trot out first the valley of the Po, the existing mud flat best known by personal experience to the feet and eyes of the tweed-clad English tourist. Everybody who has looked down upon the wide Lombard plain from the pinnacled roof of Milan Cathedral, or who has passed by rail through that monotonous level of poplars and vines between Verona and Venice, knows well what a mud flat due to inundation and gradual silting up of a valley looks like. What I want to do now is to inquire into its origin, and to follow up in fancy the same process, still in action, till it has filled the Adriatic from end to end with one great cultivable lowland.

Once upon a time (I like to be at least as precise as a fairy tale in the matter of dates) there was no Lombardy. And that time was not, geologically speaking, so very remote; for the whole valley of the Po, from Turin to the sea, consists entirely of alluvial deposits—or, in other words, of Alpine mud—which has all accumulated where it now lies at a fairly recent period. We know it is recent, because no part of Italy has ever been submerged since it began to gather there. To put it more definitely, the entire mass has almost certainly been laid down since the first appearance of man on our earth: the earliest human beings who reached the Alps or the Apennines—black savages clad in skins of extinct wild beasts—must have looked down from their slopes, with shaded eyes, not on a level plain such as we see to-day, but on a great arm of the sea which stretched like a gulf far up towards the base of the hills about Turin and Rivoli. Of this ancient sea the Adriatic forms the still unsilted portion. In other words, the great gulf which now stops short at Trieste and Venice once washed the foot of the Alps and the Apennines to the Superga at Turin, covering the sites of Padua, Ferrara, Bologna, Ravenna, Mantua, Cremona, Modena, Parma, Piacenza, Pavia, Milan, and Novara. The industrious reader who gets out his Baedeker and looks up the shaded map of North Italy which forms its frontispiece will be rewarded for his pains by a better comprehension of the district thus demarcated. The idle must be content to take my word for what follows. I pledge them my honour that I'll do my best not to deceive their trustful innocence.

It may sound at first hearing a strange thing to say so, but the whole of that vast gulf, from Turin to Venice, has been entirely filled up within the human period by the mud sheet brought down by mountain torrents from the Alps and the Apennines.

A parallel elsewhere will make this easier of belief. You have looked down, no doubt, from the garden of the hotel at Glion upon the lake of Geneva and the valley of the Rhone about Villeneuve and Aigle. If so, you can understand from personal knowledge the first great stage in the mud-filling process; for you must have observed for yourself from that commanding height that the lake once extended a great deal farther up country towards Bex and St. Maurice than it does at present. You can still trace at once on either side the old mountainous banks, descending into the plain as abruptly and unmistakably as they still descend to the water's edge at Montreux and Vevey. But the silt of the Rhone, brought down in great sheets of glacier mud (about which more anon) from the Furca and the Jungfrau and the Monte Rosa chain, has completely filled in the upper nine miles of the old lake basin with a level mass of fertile alluvium. There is no doubt about the fact: you can see it for yourself with half an eye from that specular mount (to give the Devil his due, I quote Milton's Satan): the mud lies even from bank to bank, raised only a few inches above the level of the lake, and as lacustrine in effect as the veriest geologist on earth could wish it. Indeed, the process of filling up still continues unabated at the present day where the mud-laden Rhone enters the lake at Bouveret, to leave it again, clear and blue and beautiful, under the bridge at Geneva. The little delta which the river forms at its mouth shows the fresh mud in sheets gathering thick upon the bottom. Every day this new mud-bank pushes out farther and farther into the water, so that in process of time the whole basin will be filled in, and a level plain, like that which now spreads from Bex and Aigle to Villeneuve, will occupy the entire bed from Montreux to Geneva.

Turn mentally to the upper feeders of the Po itself, and you find the same causes equally in action. You have stopped at Pallanza—Garoni's is so comfortable. Well, then, you know how every Alpine stream, as it flows, full-gorged, into the Italian lakes, is busily engaged in filling them up as fast as ever it can with turbid mud from the uplands. The basins of Maggiore, Como, Lugano, and Garda are by origin deep hollows scooped out long since during the Great Ice Age by the pressure of huge glaciers that then spread far down into what is now the poplar-clad plain of Lombardy. But ever since the ice cleared away, and the torrents began to rush headlong down the deep gorges of the Val Leventina and the Val Maggia, the mud has been hard at work, doing its level best to fill those great ice-worn bowls up again. Near the mouth of each main stream it has already succeeded in spreading a fan-shaped delta. I will not insult you by asking you at the present time of day whether you have been over the St. Gothard. In this age of trains de luxe I know to my cost everybody has been everywhere. No chance of pretending to superior knowledge about Japan or Honolulu; the tourist knows them. Very well, then; you must remember as you go past Bellinzona—revolutionary little Bellinzona with its three castled crags—you look down upon a vast mud flat by the mouth of the Ticino. Part of this mud flat is already solid land, but part is mere marsh or shifting quicksand. That is the first stage in the abolition of the lakes: the mud is annihilating them.

Maggiore, indeed, least fortunate of the three main sheets, is being attacked by the insidious foe at three points simultaneously. At the upper end, the Ticino, that furious radical river, has filled in a large arm, which once spread far away up the valley towards Bellinzona. A little lower down, the Maggia near Locarno carries in a fresh contribution of mud, which forms another fan-shaped delta, and stretches its ugly mass half across the lake, compelling the steamers to make a considerable detour eastward. This delta is rapidly extending into the open water, and will in time fill in the whole remaining space from bank to bank, cutting off the upper end of the lake about Locarno from the main basin by a partition of lowland. This upper end will then form a separate minor lake, and the Ticino will flow out of it across the intervening mud flat into the new and smaller Maggiore of our great-great-grandchildren. If you doubt it, look what the torrent of the Toce, the third assailing battalion of the persistent mud force, has already done in the neighbourhood of Pallanza. It has entirely cut off the upper end of the bay, that turns westward towards the Simplon, by a partition of mud; and this isolated upper bit forms now in our own day a separate lake, the Lago di Mergozzo, divided from the main sheet by an uninteresting mud bank. In process of time, no doubt, the whole of Maggiore will be similarly filled in by the advancing mud sheet, and will become a level alluvial plain, surrounded by mountains, and greatly admired by the astute Piedmontese cultivator.

What is going on in Maggiore is going on equally in all the other sub-Alpine lakes of the Po valley. They are being gradually filled in, every one of them, by the aggressive mud sheet. The upper end of Lugano, for example, has already been cut off, as the Lago del Piano, from the main body; and the piano itself, from which the little isolated tarn takes its name, is the alluvial mud fiat of a lateral torrent—the mud flat, in fact, which the railway from Porlezza traverses for twenty minutes before it begins its steep and picturesque climb by successive zigzags over the mountains to Menaggio. Similarly the influx of the Adda at the upper end of Como has cut off the Lago di Mezzola from the main lake, and has formed the alluvial level that stretches so drearily all around Colico. Slowly the mud fiend encroaches everywhere on the lakes; and if you look for him when you go, there you can see him actually at work every spring under your very eyes, piling up fresh banks and deltas with alarming industry, and preparing (in a few hundred thousand years) to ruin the tourist trade of Cadenabbia and Bellagio.

If we turn from the lakes themselves to the Lombard plain at large, which is an immensely older and larger basin, we see traces of the same action on a vastly greater scale. A glance at the map will show the intelligent and ever courteous reader that the 'wandering Po'—I drop into poetry after Goldsmith—flows much nearer the foot of the Apennines than of the Alps in the course of its divagations, and seems purposely to bend away from the greater range of mountains. Why is this, since everything in nature must needs have a reason? Well, it is because, when the mud first began to accumulate in the old Lombard bay of the Adriatic, there was no Po at all, whether wandering or otherwise: the big river has slowly grown up in time by the union of the lateral torrents that pour down from either side, as the growth of the mud flat brought them gradually together. Careful study of a good map will show how this has happened, especially if it has the plains and mountains distinctively tinted after the excellent German fashion. The Ticino, the Adda, the Mincio, if you look at them close, reveal themselves as tributaries of the Po, which once flowed separately into the Lombard bay; the Adige, the Piave, the Tagliamento farther along the coast, reveal themselves equally as tributaries of the future Po, when once the great river shall have filled up with its mud the space between Trieste and Venice, though for the moment they empty themselves and their store of detritus into the open Adriatic.

Fix your eyes for a moment on Venetia proper, and you will see how this has all happened and is still happening. Each mountain torrent that leaps from the Tyrolese Alps bring down in its lap a rich mass of mud, which has gradually spread over a strip of sea some forty or fifty miles wide, from the base of the mountains to the modern coast-line of the province. Near the sea—or, in other words, at the temporary outlet—it forms banks and lagoons, of which those about Venice are the best known to tourists, though the least characteristic. For miles and miles between Venice and Trieste the shifting north shore of the Adriatic consists of nothing but such accumulating mud banks. Year after year they push farther seaward, and year after year fresh islets and shoals grow out into the waves beyond the temporary deltas. In time, therefore, the gathering mud banks of these Alpine torrents must join the greater mud bank that runs rapidly seaward at the delta of the Po. As soon as they do so the rivers must rush together, and what was once an independent stream, emptying itself into the Adriatic, must become a tributary of the Po, helping to swell the waters of that great united river. The Adige has now just reached this state: its delta is continuous with the delta of the Po, and their branches interosculate. The Mincio and the Adda reached it ages since: the Piave and the Livenia will not reach it for ages. In Roman days Hatria was still on the sea: it is now some fifteen miles inland.

From all this you can gather why the existing Po flows far from the Alps and nearer the base of the Apennines. The Alpine streams in far distant days brought down relatively large floods of glacial mud; formed relatively large deltas in the old Lombard bay; filled up with relative rapidity their larger half of the basin. The Apennines, less lofty, and free from glaciers, sent down shorter and smaller torrents, laden with far less mud, and capable therefore of doing but little alluvial work for the filling in of the future Lombardy. So the river was pushed southward by the Alpine deposits of the northern streams, leaving the great plains of Cisalpine Gaul spread away to the north of it.

And this land-making action is ceaseless and continuous. About Venice, Chioggia, Maestra, Comacchio, the delta of the Po is still spreading seaward. In the course of ages—if nothing unforeseen occurs meanwhile to prevent it—the Alpine mud will have filled in the entire Adriatic; and the Ionian Isles will spring like isolated mountain ridges from the Adriatic plain, as the Euganean hills—those 'mountains Euganean' where Shelley 'stood listening to the pæan with which the legioned rocks did hail the sun's uprise majestical'—spring in our own time from the dead level of Lombardy. Once they in turn were the Euganean islands, and even now to the trained eye of the historical observer they stand up island-like from the vast green plain that spreads flat around them.

Perhaps it seems to you a rather large order to be asked to believe that Lombardy and Venetia are nothing more than an outspread sheet of deep Alpine mud. Well, there is nothing so good for incredulity, don't you know, as capping the climax. If a man will not swallow an inch of fact, the best remedy is to make him gulp down an ell of it. And, indeed, the Lombard plain is but an insignificant mud flat compared with the vast alluvial plains of Asiatic and American rivers. The alluvium of the Euphrates, of the Mississippi, of the Hoang Ho, of the Amazons would take in many Lombardies and half-a-dozen Venetias without noticing the addition. But I will insist upon only one example—the rivers of India, which have formed the gigantic deep mud flat of the Ganges and the Jumna, one of the very biggest on earth, and that because the Himalayas are the highest and newest mountain chain exposed to denudation. For, as we saw foreshadowed in the case of the Alps and Apennines, the bigger the mountains on which we can draw the greater the resulting mass of alluvium. The Rocky Mountains give rise to the Missouri (which is the real Mississippi); the Andes give rise to Amazons and the La Plata; the Himalayas give rise to the Ganges and the Indus. Great mountain, great river, great resulting mud sheet.

At a very remote period, so long ago that we cannot reduce it to any common measure with our modern chronology, the southern table-land of India—the Deccan, as we call it—formed a great island like Australia, separated from the continent of Asia by a broad arm of the sea which occupied what is now the great plain of Bengal, the North-West, and the Punjaub. This ancient sea washed the foot of the Himalayas, and spread south thence for 600 miles to the base of the Vindhyas. But the Himalayas are high and clad with gigantic glaciers. Much ice grinds much mud on those snow-capped summits. The rivers that flowed from the Roof of the World carried down vast sheets of alluvium, which formed fans at their mouths, like the cones still deposited on a far smaller scale in the Lake of Geneva by little lateral torrents. Gradually the silt thus brought down accumulated on either side, till the rivers ran together into two great systems—one westward—the Indus, with its four great tributaries, Jhelum, Chenab, Ravee, Sutlej; one eastward, the Ganges, reinforced lower down by the sister streams of the Jumna and the Brahmapootra. The colossal accumulation of silt thus produced filled up at last all the great arm of the sea between the two mountain chains, and joined the Deccan by slow degrees to the continent of Asia. It is still engaged in filling up the Bay of Bengal on one side by the detritus of the Ganges, and the Arabian Sea on the other by the sand-banks of the Indus.

In the same way, no doubt, the silt of the Thames, the Humber, the Rhine, and the Meuse tend slowly (bar accidents) to fill up the North Sea, and anticipate Sir Edward Watkin by throwing a land bridge across the English Channel. If ever that should happen, then history will have repeated itself, for it is just so that the Deccan was joined to the mainland of Asia.

One question more. Whence comes the mud? The answer is, Mainly from the detritus of the mountains. There it has two origins. Part of it is glacial, part of it is leaf-mould. In order to feel we have really got to the very bottom of the mud problem—and we are nothing if not thorough—we must examine in brief these two separate origins.

The glacier mud is of a very simple nature. It is disintegrated rock, worn small by the enormous millstone of ice that rolls slowly over the bed, and deposited in part as 'terminal moraine' near the summer melting-point. It is the quantity of mud thus produced, and borne down by mountain torrents, that makes the alluvial plains collect so quickly at their base. The mud flats of the world are in large part the wear and tear of the eternal hills under the planing action of the eternal glaciers.

But let us be just to our friends. A large part is also due to the industrious earth-worm, whose place in nature Darwin first taught us to estimate at its proper worth. For there is much detritus and much first-rate soil even on hills not covered by glaciers. Some of this takes its origin, it is true, from disintegration by wind or rain, but much more is caused by the earth-worm in person. That friend of humanity, so little recognized in his true light, has a habit of drawing down leaves into his subterranean nest, and there eating them up, so as to convert their remains into vegetable mould in the form of worm-casts. This mould, the most precious of soils, gets dissolved again by the rain, and carried off in solution by the streams to the sea or the lowlands, where it helps to form the future cultivable area. At the same time the earthworms secrete an acid, which acts upon the bare surface of rock beneath, and helps to disintegrate it in preparation for plant life in unfavourable places. It is probable that we owe almost more on the whole to these unknown but conscientious and industrious annelids than even to those 'mills of God' the glaciers, of which the American poet justly observes that though they grind slowly, yet they grind exceedingly small.

In the last resort, then, it is mainly on mud that the life of humanity in all countries bases itself. Every great plain is the alluvial deposit of a great river, ultimately derived from a great mountain chain. The substance consists as a rule of the débris of torrents, which is often infertile, owing to its stoniness and its purely mineral character; but wherever it has lain long enough to be covered by earth-worms with a deep black layer of vegetable mould, there the resulting soil shows the surprising fruitfulness one gets (for example) in Lombardy, where twelve crops a year are sometimes taken from the meadows. Everywhere and always the amount and depth of the mud is the measure of possible fertility; and even where, as in the Great American Desert, want of water converts alluvial plains into arid stretches of sand-waste, the wilderness can be made to blossom like the rose in a very few years by artificial irrigation. The diversion of the Arkansas River has spread plenty over a vast sage scrub; the finest crops in the world are now raised over a tract of country which was once the terror of the traveller across the wild west of America.

THE GREENWOOD TREE

It is a common, not to say a vulgar error, to believe that trees and plants grow out of the ground. And of course, having thus begun by calling it bad names, I will not for a moment insult the intelligence of my readers by supposing them to share so foolish a delusion. I beg to state from the outset that I write this article entirely for the benefit of Other People. You and I, O proverbially Candid and Intelligent One, it need hardly be said, are better informed. But Other People fall into such ridiculous blunders that it is just as well to put them on their guard beforehand against the insidious advance of false opinions. I have known otherwise good and estimable men, indeed, who for lack of sound early teaching on this point went to their graves with a confirmed belief in the terrestrial origin of all earthly vegetation. They were probably victims of what the Church in its succinct way describes and denounces as Invincible Ignorance.

Now, the reason why these deluded creatures supposed trees to grow out of the ground, instead of out of the air, is probably only because they saw their roots there.

Of course, when people see a wallflower rooted in the clefts of some old church tower, they don't jump at once to the inane conclusion that it is made of rock—that it derives its nourishment direct from the solid limestone; nor when they observe a barnacle hanging by its sucker to a ship's hull, do they imagine it to draw up its food incontinently from the copper bottom. But when they see that familiar pride of our country, a British oak, with its great underground buttresses spreading abroad through the soil in every direction, they infer at once that the buttresses are there, not—as is really the case—to support it and uphold it, but to drink in nutriment from the earth beneath, which is just about as capable of producing oak-wood as the copper plate on the ship's hull is capable of producing the flesh of a barnacle. Sundry familiar facts about manuring and watering, to which I will return later on, give a certain colour of reasonableness, it is true, to this mistaken inference. But how mistaken it really is for all that, a single and very familiar little experiment will easily show one.