by Grant Allen
The Great Salt Lake of Utah, sacred to the memory of Brigham Young, gives us an example of a modern saline sheet of very different origin, since it is in fact not a branch of the sea at all, but a mere shrunken remnant of a very large fresh-water lake system, like that of the still-existing St. Lawrence chain. Once upon a time, American geologists say, a huge sheet of water, for which they have even invented a definite name, Lake Bonneville, occupied a far larger valley among the outliers of the Rocky Mountains, measuring 300 miles in one direction by 180 miles in the other. Beside this primitive Superior lay a second great sheet — an early Huron — (Lake Lahontan, the geologists call it) almost as big, and equally of fresh water. By-and-by — the precise dates are necessarily indefinite — some change in the rainfall, unregistered by any contemporary ‘New York Herald,’ made the waters of these big lakes shrink and evaporate. Lake Lahontan shrank away like Alice in Wonderland, till there was absolutely nothing left of it; Lake Bonneville shrank till it attained the diminished size of the existing Great Salt Lake. Terrace after terrace, running in long parallel lines on the sides of the Wahsatch Mountains around, mark the various levels at which it rested for awhile on its gradual downward course. It is still falling indeed; and the plain around is being gradually uncovered, forming the white salt-encrusted shore with which all visitors to the Mormon city are so familiar.
But why should the water have become briny? Why should the evaporation of an old Superior produce at last a Great Salt Lake? Well, there is a small quantity of salt in solution even in the freshest of lakes and ponds, brought down to them by the streams or rivers; and, as the water of the hypothetical Lake Bonneville slowly evaporated, the salt and other mineral constituents remained behind. Thus the solution grew constantly more and more concentrated, till at the present day it is extremely saline. Professor Geikie (to whose works the present paper is much indebted) found that he floated on the water in spite of himself; and the under sides of the steps at the bathing-places are all encrusted with short stalactites of salt, produced from the drip of the bathers as they leave the water. The mineral constituents, however, differ considerably in their proportions from those found in true salt lakes of marine origin; and the point at which the salt is thrown down is still far from having been reached. Great Salt Lake must simmer in the sun for many centuries yet before the point arrives at which (as cooks say) it begins to settle.
That is the way in which deposits of salt are being now produced on the world’s surface, in preparation for that man of the future who, as we learn from a duly constituted authority, is to be hairless, toothless, web-footed, and far too respectable ever to be funny. Man of the present derives his existing salt-supply chiefly from beds of rock-salt similarly laid down against his expected appearance some hundred thousand æons or so ago. (An æon is a very convenient geological unit indeed to reckon by; as nobody has any idea how long it is, they can’t carp at you for a matter of an æon or two one way or the other.) Rock-salt is found in most parts of the world, in beds of very various ages. The great Salt Range of the Punjaub is probably the earliest in date of all salt deposits; it was laid down at the bottom of some very ancient Asiatic Mediterranean, whose last shrunken remnant covered the upper basin of the Indus and its tributaries during the Silurian age. Europe had then hardly begun to be; and England was probably still covered from end to end by the primæval ocean. From this very primitive salt deposit the greater part of India and Central Asia is still supplied; and the Indian Government makes a pretty penny out of the dues in the shape of the justly detested salt-tax — a tax especially odious because it wrings the fraction of a farthing even from those unhappy agricultural labourers who have never tasted ghee with their rice.
The thickness of the beds in each salt deposit of course depends entirely upon the area of the original sea or salt-lake, and the length of time during which the evaporation went on. Sometimes we may get a mere film of salt; sometimes a solid bed six hundred feet thick. Perfectly pure rock-salt is colourless and transparent; but one doesn’t often find it pure. Alas for a degenerate world! even in its original site, Nature herself has taken the trouble to adulterate it beforehand. (If she hadn’t done so, one may be perfectly sure that commercial enterprise would have proved equal to the occasion in the long run.) But the adulteration hasn’t spoilt the beauty of the salt; on the contrary, it serves, like rouge, to give a fine fresh colour where none existed. When iron is the chief colouring matter, rock-salt assumes a beautiful clear red tint; in other cases it is emerald green or pale blue. As a rule, salt is prepared from it for table by a regular process; but it has become a fad of late with a few people to put crystals of native rock-salt on their tables; and they decidedly look very pretty, and have a certain distinctive flavour of their own that is not unpleasant.
Our English salt supply is chiefly derived from the Cheshire and Worcestershire salt-regions, which are of triassic age. Many of the places at which the salt is mined have names ending in wich, such as Northwich, Middlewich, Nantwich, Droitwich, Netherwich, and Shirleywich. This termination wich is itself curiously significant, as Canon Isaac Taylor has shown, of the necessary connection between salt and the sea. The earliest known way of producing salt was of course in shallow pans on the sea-shore, at the bottom of a shoal bay, called in Norse and Early English a wick or wich; and the material so produced is still known in trade as bay-salt. By-and-by, when people came to discover the inland brine-pits and salt mines, they transferred to them the familiar name, a wich; and the places where the salt was manufactured came to be known as wych-houses. Droitwich, for example, was originally such a wich, where the droits or dues on salt were paid at the time when William the Conqueror’s commissioners drew up their great survey for Domesday Book. But the good, easy-going mediæval people who gave these quaint names to the inland wiches had probably no idea that they were really and truly dried-up bays, and that the salt they mined from their pits was genuine ancient bay-salt, the deposit of an old inland sea, evaporated by slow degrees a countless number of ages since, exactly as the Dead Sea and the Great Salt Lake are getting evaporated in our own time.
Such, nevertheless, is actually the case. A good-sized Caspian used to spread across the centre of England and north of Ireland in triassic times, bounded here and there, as well as Dr. Hull can make out, by the Welsh Mountains, the Cheviots, and the Donegal Hills, and with the Peak of Derbyshire and the Isle of Man standing out as separate islands from its blue expanse. (We will beg the question that the English seas were then blue. They are certainly marked so in a very fine cerulean tint on Dr. Hull’s map of Triassic Britain.) Slowly, like most other inland seas, this early British Caspian began to lose weight and to shrivel away to ever smaller dimensions. In Devonshire, where it appears to have first dried up, we get no salt, but only red marl, with here and there a cubical cast, filling a hole once occupied by rock-salt, though the percolation of the rain has long since melted out that very soluble substance, and replaced it by a mere mould in the characteristic square shape of salt crystals. But Worcestershire and Cheshire were the seat of the inland sea when it had contracted to the dimensions of a mere salt lake, and begun to throw down its dissolved saline materials. One of the Cheshire beds is sometimes a hundred feet thick of almost pure and crystalline rock-salt. The absence of fossils shows that animals must have had as bad a time of it there as in the Dead Sea of our modern Palestine. The Droitwich brine-pits have been known for many centuries, since they were worked (and taxed) even before the Norman Conquest, as were many other similar wells elsewhere. But the actual mining of rock-salt as such in England dates back only as far as the reign of King Charles II. of blessed memory, or more definitely to the very year in which the ‘Pilgrim’s Progress’ was conceived and written by John Bunyan. During that particular summer, an enterprising person at Nantwich had sunk a shaft for coal, which he failed to find; but on his way down he came unexpectedly across the bed of rock-salt, then for the first time discovered as a native mineral. Since t
hat fortunate accident the beds have been so energetically worked and the springs so energetically pumped that some of the towns built on top of them have got undermined, and now threaten from year to year, in the most literal sense, to cave in. In fact, one or two subsidences of considerable extent have already taken place, due in part no doubt to the dissolving action of rain water, but in part also to the mode of working. The mines are approached by a shaft; and, when you get down to the level of the old sea bottom, you find yourself in a sort of artificial gallery, whose roof, with all the world on top of it, is supported every here and there by massive pillars about fifteen feet thick. Considering that the salt lies often a hundred and fifty yards deep, and that these pillars have to bear the weight of all that depth of solid rock, it is not surprising that subsidences should sometimes occur in abandoned shafts, where the water is allowed to collect, and slowly dissolve away the supporting columns.
Salt is a necessary article of food for animals, but in a far less degree than is commonly supposed. Each of us eats on an average about ten times as much salt as we actually require. In this respect popular notions are as inexact as in the very similar case of the supply of phosphorus. Because phosphorus is needful for brain action, people jump forthwith to the absurd conclusion that fish and other foods rich in phosphates ought to be specially good for students preparing for examination, great thinkers, and literary men. Mark Twain indeed once advised a poetical aspirant, who sent him a few verses for his critical opinion, that fish was very feeding for the brains; he would recommend a couple of young whales to begin upon. As a matter of fact, there is more phosphorus in our daily bread than would have sufficed Shakespeare to write ‘Hamlet,’ or Newton to discover the law of gravitation. It isn’t phosphorus that most of us need, but brains to burn it in. A man might as well light a fire in a carriage, because coal makes an engine go, as hope to mend the pace of his dull pate by eating fish for the sake of the phosphates.
The question still remains, How did the salt originally get there? After all, when we say that it was produced, as rock-salt, by evaporation of the water in inland seas, we leave unanswered the main problem, How did the brine in solution get into the sea at all in the first place? Well, one might almost as well ask, How did anything come to be upon the earth at any time, in any way? How did the sea itself get there? How did this planet swim into existence at all? In the Indian mythology the world is supported upon the back of an elephant, who is supported upon the back of a tortoise; but what the tortoise in the last resort is supported upon the Indian philosophers prudently say not. If we once begin thus pushing back our inquiries into the genesis of the cosmos, we shall find our search retreating step after step ad infinitum. The negro preacher, describing the creation of Adam, and drawing slightly upon his imagination, observed that when our prime forefather first came to consciousness he found himself ‘sot up agin a fence.’ One of his hearers ventured sceptically to ejaculate, ‘Den whar dat fence come from, ministah?’ The outraged divine scratched his grey wool reflectively for a moment, and replied, after a pause, with stern solemnity, ‘Tree more ob dem questions will undermine de whole system ob teology.’
However, we are not permitted humbly to imitate the prudent reticence of the Indian philosophers. In these days of evolution hypotheses, and nebular theories, and kinetic energy, and all the rest of it, the question why the sea is salt rises up irrepressible and imperatively demands to get itself answered. There was a sapient inquirer, recently deceased, who had a short way out of this difficulty. He held that the sea was only salt because of all the salt rivers that run into it. Considering that the salt rivers are themselves salted by passing through salt regions, or being fed by saline springs, all of which derive their saltness from deposits laid down long ago by evaporation from earlier seas or lake basins, this explanation savours somewhat of circularity. It amounts in effect to saying that the sea is salt because of the large amount of saline matter which it holds in solution. Cheese is also a caseous preparation of milk; the duties of an archdeacon are to perform archidiaconal functions; and opium puts one to sleep because it possesses a soporific virtue.
Apart from such purely verbal explanations of the saltness of the sea, however, one can only give some such account of the way it came to be ‘the briny’ as the following: —
This world was once a haze of fluid light, as the poets and the men of science agree in informing us. As soon as it began to cool down a little, the heavier materials naturally sank towards the centre, while the lighter, now represented by the ocean and the atmosphere, floated in a gaseous condition on the outside. But the great envelope of vapour thus produced did not consist merely of the constituents of air and water; many other gases and vapours mingled with them, as they still do to a far less extent in our existing atmosphere. By-and-by, as the cooling and condensing process continued, the water settled down from the condition of steam into one of a liquid at a dull red heat. As it condensed, it carried down with it a great many other substances, held in solution, whose component elements had previously existed in the primitive gaseous atmosphere. Thus the early ocean which covered the whole earth was in all probability not only very salt, but also quite thick with other mineral matters close up to the point of saturation. It was full of lime, and raw flint, and sulphates, and many other miscellaneous bodies. Moreover, it was not only just as salt as at the present day, but even a great deal salter. For from that time to this evaporation has constantly been going on in certain shallow isolated areas, laying down great beds of gypsum and then of salt, which still remain in the solid condition, while the water has, of course, been correspondingly purified. The same thing has likewise happened in a slightly different way with the lime and flint, which have been separated from the water chiefly by living animals, and afterwards deposited on the bottom of the ocean in immense layers as limestone, chalk, sandstone, and clay.
Thus it turns out that in the end all our sources of salt-supply are alike ultimately derived from the briny ocean. Whether we dig it out as solid rock-salt from the open quarries of the Punjaub, or pump it up from brine-wells sunk into the triassic rocks of Cheshire, or evaporate it direct in the salt-pans of England and the shallow salines of the Mediterranean shore, it is still at bottom essentially sea-salt. However distant the connection may seem, our salt is always in the last resort obtained from the material held in solution in some ancient or modern sea. Even the saline springs of Canada and the Northern States of America, where the wapiti love to congregate, and the noble hunter lurks in the thicket to murder them unperceived, derive their saltness, as an able Canadian geologist has shown, from the thinly scattered salts still retained among the sediments of that very archaic sea whose precipitates form the earliest known life-bearing rocks. To the Homeric Greek, as to Mr. Dick Swiveller, the ocean was always the briny: to modern science, on the other hand (which neither of those worthies would probably have appreciated at its own valuation), the briny is always the oceanic. The fossil food which we find to-day on all our dinner-tables dates back its origin primarily to the first seas that ever covered the surface of our planet, and secondarily to the great rock deposits of the dried-up triassic inland sea. And yet even our men of science habitually describe that ancient mineral as common salt.
OGBURY BARROWS
We went to Ogbury Barrows on an archæological expedition. And as the very name of archæology, owing to a serious misconception incidental to human nature, is enough to deter most people from taking any further interest in our proceedings when once we got there, I may as well begin by explaining, for the benefit of those who have never been to one, the method and manner of an archæological outing.
The first thing you have to do is to catch your secretary. The genuine secretary is born, not made; and therefore you have got to catch him, not to appoint him. Appointing a secretary is pure vanity and vexation of spirit; you must find the right man made ready to your hand; and when you have found him you will soon see that he slips into the onerous duti
es of the secretariat as if to the manner born, by pure instinct. The perfect secretary is an urbane old gentleman of mature years and portly bearing, a dignified representative of British archæology, with plenty of money and plenty of leisure, possessing a heaven-born genius for organisation, and utterly unhampered by any foolish views of his own about archæological research or any other kindred subject. The secretary who archæologises is lost. His business is not to discourse of early English windows or of palæolithic hatchets, of buried villas or of Plantagenet pedigrees, of Roman tile-work or of dolichocephalic skulls, but to provide abundant brakes, drags, and carriages, to take care that the owners of castles and baronial residences throw them open (with lunch provided) to the ardent student of British antiquities, to see that all the old ladies have somebody to talk to, and all the young ones somebody to flirt with, and generally to superintend the morals, happiness, and personal comfort of some fifty assorted scientific enthusiasts. The secretary who diverges from these his proper and elevated functions into trivial and puerile disquisitions upon the antiquity of man (when he ought rather to be admiring the juvenility of woman), or the precise date of the Anglo-Saxon conquest (when he should by rights be concentrating the whole force of his massive intellect upon the arduous task of arranging for dinner), proves himself at once unworthy of his high position, and should forthwith be deposed from the secretariat by public acclamation.
Having once entrapped your perfect secretary, you set him busily to work beforehand to make all the arrangements for your expected excursion, the archæologists generally cordially recognising the important principle that he pays all the expenses he incurs out of his own pocket, and drives splendid bargains on their account with hotel-keepers, coachmen, railway companies, and others to feed, lodge, supply, and convey them at fabulously low prices throughout the whole expedition. You also understand that the secretary will call upon everybody in the neighbourhood you propose to visit, induce the rectors to throw open their churches, square the housekeepers of absentee dukes, and beard the owners of Elizabethan mansions in their own dens. These little preliminaries being amicably settled, you get together your archæologists and set out upon your intended tour.
