Chapter 23 - The Adventures of a Lost Family in the Wilderness by Mayne Reid
The Salt Spring
“We had now arrived on the banks of the salt creek; but as we saw the cliff close by, and knew that we must be near the spring which supplied this little rivulet, we resolved to travel on to the fountain-head. A few hundred yards farther brought us to the spring, and it was well worth travelling a little farther to see.
“Near the bottom of the cliff were several round objects, looking like half globes, or bowls turned upon their mouths. They were of a whitish colour, resembling white quartz rock; and of all sizes, from that of a large baking oven to the size of a wooden dish. In the top of each there was a round cavity—like a little crater of a volcano—and in this the blue water bubbled and boiled as though a hot fire was in the ground underneath them. There were in all nearly twenty of these, but many of them were without the crater-like cavity in the top; and through the latter, of course, no water escaped to the creek. These were old ones, that had ceased to run.
“It was evident that these oven-looking mounds had been formed by the water itself, which had been depositing the sediment that formed them for many, many years. Around some of them there grew beautiful plants and shrubs, whose leaves and flowers hung over, trailing in the water; and from the cliff above long vines crept out, covered with gay scarlet blossoms. Bushes of wild currants grew all around, and the fragrance of their leaves scented the air. It was altogether a sweet, cool spot, and filled us with feelings of enjoyment.
“After we had satisfied our curiosity in examining these objects, we prepared to make our salt. Frank and Harry collected armfuls of dry wood for the fire, while Cudjo erected a crane in his usual fashion. Upon this the kettle was suspended, and filled with crystal water out of one of the natural basins. The fire soon blazed under it, and we had nothing more to do than wait until the evaporation should be completed by boiling.
“For this purpose we chose a spot where the ground was carpeted with a soft green turf; and upon it we all sat down to wait the result.
“I need not say that in this we had a deep interest, amounting, in truth, to anxiety. It might not be salt after all. The water tasted salt—that is true. But so, too, would water impregnated by the sulphate of magnesia or the sulphate of soda. When evaporated we might find one or other of these substances.
“‘What is the sulphate of magnesia, papa?’ inquired Frank.
“‘Perhaps you would know it better by the name of Epsom salts!’ rejoined his mother, with a knowing smile.
“‘Bah!’ returned he, with a grin upon his face, ‘I hope it won’t turn out that. But what sort of thing, then, is the sulphate of soda?’
“‘That is the scientific name for Glauber’s salts.’
“‘Worse still! I don’t think we stand in need of either. Do we, Harry?’
“‘Not a bit of it,’ responded Harry, also grinning at the thought of these well-known specifics. ‘I would rather it should turn out saltpetre and sulphur. Then we could make lots of gunpowder.’
“Harry was a great shot—as we have seen—and one of his fears was, that our stock of powder would run out.
“‘Do not wish for that, Harry,’ said his mother. ‘Gunpowder we can do very well without. Let us hope for something more necessary to us at present.’
“With such-like conversation we passed the time, while we watched the steaming kettle with feelings of anxious expectation.
“For myself, I had some reliance upon a fact which I had observed years before, and had regarded as singular. It was this. I believe the Creator has so disposed it, that salt, so essential to animal life, is to be found in all parts of the globe, either in rocks, springs, standing lakes, incrustations, or in the ocean itself. No part of the earth, of great extent, is without it; and I had noticed in the interior territories of the American continent—where the sea is too distant to be visited by animals—that Nature has provided numerous salt springs, or ‘licks,’ as they are termed in the language of the country. These springs from time immemorial have been the meeting-places of the wild creatures of the forest and prairie, who resort thither to drink their waters, or lick the saline soil through which these waters run. Hence their common name of ‘licks.’ Here, then, was a valley whose four-footed inhabitants never roamed beyond its borders. I felt confident that Nature had provided for their wants and cravings by giving them everything necessary to their existence, and, among other necessities, that one which we were now in search of ourselves—salt. In other words, but that this was a salt spring, or there existed some other such in the valley, these creatures would not have been found within it. I took the opportunity to point out this theory to my boys, as well as to show them—what I myself clearly recognised in it—the hand of the Creator. It rendered them confident that, when we had evaporated our water, we should get salt for our pains.
“‘Papa,’ inquired Frank, who was a great naturalist, ‘I should like to know what makes this little rivulet run salt water.’
“‘No doubt,’ I replied, ‘the water you see gushing forth has just been passing through vast beds or rock-salt, and has become impregnated with it.’
“‘Rock-salt! and is the salt we use found in rocks?’
“‘Not all of it, though great quantities are. There are beds of rock-salt found in many countries—in England, and the East Indies, in Russia, and Hungary, and Spain; and it has also been discovered in vast quantities in this very Desert we are now dwelling in. These beds of rock-salt, when worked to supply salt, are called salt-mines. The most celebrated are in Poland, near the city of Cracow. These have been worked for seven hundred years; and there is enough left in them to supply all the world for many centuries yet to come. These mines are said to be very beautiful—lit up, as they are, by numerous lamps. The rock has been excavated by the miners into all sorts of shapes. Houses, chapels, columns, obelisks, and many other ornamental forms of buildings, have been made; and these, when illuminated by lamps and torches, appear as splendid and brilliant as the palaces of Aladdin.’
“‘Oh! I should like so much to see them!’ cried Harry, in a transport.
“‘But, papa,’ inquired Frank, who always sought after information on such subjects, ‘I never saw any of this rock-salt. How is it that it comes to us always crushed, or in great bricks, as if it had been baked? Do they break it fine before it is sent to market from the mines?’
“‘In some of these mines nothing more is required than to crush the rock; in others, however, the rock is not pure salt, but mixed with other substances, as oxide of iron and clay. In these cases it is first dissolved in water, to separate it from such impurities, and then evaporated back again into salt, precisely as we are doing now.’
“‘What colour is the salt-rock, papa?’
“‘When pure it is white; but it assumes various colours, according to what substances may be found mixed with it. It is often yellow, and flesh-coloured, and blue.’
“‘How pretty it must be!’ exclaimed Harry; ‘like precious stones, I declare.’
“‘Yes, it is a precious stone,’ rejoined his brother; ‘more precious, I take it, than all the diamonds in the world. Is it not, papa?’
“‘You are quite right,’ I replied. ‘Salt-rock is more valuable to the human race than diamonds; though they, too, have an absolute value, besides their value as a mere ornament. There are some important uses in arts and manufactures to which they can be applied.’
“‘But, papa,’ again inquired Frank, determined to know everything he could about the article of salt, ‘I have heard that salt is made of sea-water. Is it so?’
“‘Vast quantities of it.’
“‘How is it made?’
“‘There are three ways of obtaining it:—First, in warm climates, where the sun is strong, the sea-water is collected into shallow pools, and there left until it is evaporated by the sun’s rays. The ground where these pools are made must neither be muddy nor porous, else the salt would get mixed with the mud and sand. Of course the people who manufacture it in this way take care to choose firm, hard ground for the bottoms of their pools. There are sluices attached to these pools by which any water that may not evaporate is drawn off. Salt is made in this manner in many southern countries—in Spain and Portugal, in France, and other countries that lie around the Mediterranean; also in India, China, Siam, and the island of Ceylon.
“‘The second way of making salt from sea-water is precisely the same as that I have described—except that, instead of these artificial pools, the evaporation takes place in broad tracts of country over which the sea has spread in time of high springtides. When the sea falls again to its proper level, it leaves behind it a quantity of water in these tracts, which is evaporated by the sun, leaving behind it fields of pure salt. Nothing remains to be done but to scrape this salt into heaps and cart it off; and at the next spring-tide a fresh influx of sea-water produces a new crop of salt, and so on. This kind is better than that which is made in the artificial pools—though neither of them is equal to the salt of the mines. They are both known in commerce under the name of “bay-salt,” to distinguish them from the “rock-salt” of the mines. Great natural beds of the bay-salt are found in the Cape de Verde islands; also in Turk’s island and Saint Martin’s in the West Indies, and on Kangaroo Island, near the coast of Australia.
“‘There is still a third plan of making salt out of the sea. That is, by boiling the water, as we are doing; but this makes the worst of all salt; besides, it is far more expensive to manufacture salt in this way than to buy it from other countries. Indeed, this last plan would never be adopted, were it not that some foolish governments force their people to pay a heavy duty for importing salt into their country, thus making it still cheaper for them, costly as it is, to manufacture the article at home.’
“‘What makes the sea salt, papa?’
“‘That is one of the phenomena about which naturalists have a difference of opinion. Some of them say there are vast beds of salt at the bottom which keep the water always impregnated. I think this notion is very childish; and they who hold it offer only childish arguments to support it. Others assert that the salt water of the ocean is a primitive fluid—that it was always as it now is—which you will perceive is giving no reason at all, more than saying, “it is salt, because it was salt always.” This is an equally irrational theory. Others, again, believe that the saltness of the ocean is caused by the flowing into it of salt rivers. These, I think, hold the true opinion; but unfortunately they have failed, as far as I know, to answer the objections which have been raised against it. Your papa has reflected a good deal upon this subject, and believes that he can explain away all the difficulties that oppose this last theory. Probably he may take an early opportunity of doing so; but it will require more time than he can spare at present.’
“‘Is the sea equally salt at all places?’ inquired the philosopher Frank, after a short pause, during which he had been busily reflecting on what had been said.
“‘No; it is more so at the Equator than in the colder regions around the Poles. It is less salt in gulfs and inland seas than in the open ocean. This I believe I can also explain, because it would support the theory regarding the rivers of which we have just spoken. The difference of saltness in different parts of the sea is, however, very trifling.’
“‘How much salt is there in the sea-water?’
“‘Three and a half per cent nearly. That is, if you boil down one hundred pounds of sea-water, it will yield you about three pounds and a half of salt.’
“‘But are there not many lakes and brine-springs that contain a far greater proportion than that?’
“‘Many. There is a large lake lying in this very Desert, to the north-west of where we are, called the “Great Salt Lake.” The waters of that lake are more than one-third pure salt. There are many springs and rivers that contain a greater proportion than the ocean itself. It is to be hoped that our own little creek here will yield better than it.—But come! let us see how the kettle boils. We had almost forgotten it.’
“We approached our kettle, and lifted the lid. To our great joy, a scum was floating on the top, very much like crystals of ice forming upon half melted snow. Some of it was skimmed off and applied to our lips. Joy! it was salt—the pure chloride of sodium—equal to the best ever shipped from Turk’s Island.”