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The History of Salt
We have thus sufficient evidence before us to prove that salt or sea water does not totally destroy the vitality of seeds when they are in a dry state, that some of them will float for 90 days, and when planted subsequently will germinate; but that when not dry they will sink immediately. We may, therefore, justly conclude from the result of these experiments that salt is not noxious to vegetable life, neither does it destroy the latent principle of procreation which exists in them; and that though the process of germination may be retarded, and kept in a state of abeyance, it is not virtually annihilated, as one would feel inclined to predict, by the prolonged immersion of seeds in salt-water, be they dried or fresh.
Darwin’s experiments were afterwards verified, for he states that subsequently M. Martens tried “similar ones, but in a much better manner, for he placed the seeds in a box in the actual sea, so that they were alternately wet and exposed to the air like really floating plants. He tried 98 seeds, mostly different from mine; but he chose many large fruits and likewise seeds from plants which live near the sea; and this would have favoured both the average length of their flotation, and their resistance to the injurious action of the salt water. On the other hand, he did not previously dry the plants or branches with the fruit; and this, as we have seen, would have caused some of them to have floated much longer. The result was that 18/98 of his seeds of different kinds floated for 42 days, and were then capable of germination. But I do not doubt that plants exposed to the waves would float for a less time than those protected from violent movement as in our experiments. Therefore it would, perhaps, be safe to assume that the seeds of about 10/100 parts of a flora, after having been dried, could be floated across a space of 900 miles in width, and would then germinate. The fact of the larger fruits often floating longer than the small, is interesting; as plants with large seeds or fruit which, as Alph. de Candolle has shown, generally have restricted ranges, could hardly be transported by other means.”
Darwin’s experiments show us that salt or sea water does not entirely extirpate the life which is dormant in seeds, and those of Martens prove that seeds may be immersed in sea-water itself and yet retain the power of germination; and that when dry they may even float for 900 miles, and germinate when planted; developing into plants at the usual period of time allotted by nature!
In Cheshire it is a custom to let out the water of the salt-springs after rain, in order to improve the character of the soil and make it more productive. If we call to mind the preservative properties of salt and the purifying action which it possesses, with regard to animal and vegetable substances, we need not at all be surprised at the above use to which it is put by the agriculturists of Cheshire. The reader, perhaps, would like to know why it is used after rain. After a heavy shower, and more especially in the country, every insect leaves its little secluded habitation: the bee is once more on the wing; the spider resumes his usual central position in his web; flies of all sizes buzz here and there in search of food or for more secure homes; every bush is alive with its usual occupants; the lofty tree is once more the tenement of song; the caterpillar crawls on his solitary way; the ant trudges along on the gravel-path; the snail emerges from his retreat and plods slowly to another home; and the earth-worm raises itself on the lawn; all with one accord hail the reappearance of sunshine, and show signs, however feeble, of joy that the rain-cloud has passed and that the landscape has resumed its beauties, and the sky its gold and azure. The earth after rain, and particularly in spring and summer, teems with almost reanimated life, both with that which is harmless and with that which is hurtful, so that the Cheshire custom is one which cannot be too highly recommended, for when the soil is saturated with moisture, a soluble salt like the chloride of sodium, already in a state of solution, sinks in more rapidly, and permeates it more thoroughly than if it were merely sprinkled over the surface; and such insects as are associated with or which live in the earth are speedily eliminated, or are forced to seek shelter at a greater depth, where they ultimately die by reason of their inability to obtain their proper sustenance or the unsuitableness of their new abode.
There is a plant called Halimodendron which only grows in the dry, naked salt-fields by the river Irtysh, in Siberia; it is a genus of the Leguminosæ, and has purple flowers. Saltwort, or Salsola, (salsus, salt) is chiefly maritime, and the kelp of our shores is principally obtained from it. At one time the carbonate of soda was derived from this kelp or barilla, the ashes being obtained from burning sea-weeds and a species of Salsola; but now it is almost invariably made from common salt, by adding sulphuric acid, and so converting the chloride of sodium into a sulphate, and afterwards, by combustion with chalk and small coal, resolving it into a sulphide, and then into a carbonate. It is manufactured on a very large scale, and is an important staple of commerce. From it is obtained a most important drug, the bicarbonate of soda, the efficacy of which everyone, more or less, has once in a lifetime experienced.
This kelp has been put to a fraudulent use, for Sir Robert Christison tells us that disease has been traced to an impure kind of salt, in which, when investigated, the hydriodate of soda was detected, resulting, he says, from an inferior salt obtained from kelp.52
In all those districts which are intersected by salt marshes, there is almost a complete absence of miasmatic effluvia, though, as a natural consequence, the vegetation is not of that rank luxuriance which is invariably to be seen in other marsh lands; because, whenever the soil is in a state of moisture, it is always covered with all kinds of weeds and useless plants, which altogether stop the growth of those which are of utility to the agriculturist.
In the case of salt marshes it is the reverse, and the neighbourhood is perfectly free from those endemic diseases which are prevalent in such localities as the fen-country, and other similar districts; for the atmosphere is pure, and the soil comparatively dry, and intermittent fever is unknown.
CHAPTER VII
MEDICINAL AND DIETETIC PROPERTIES
Salt, except by the ignorant, is generally acknowledged to be a condiment, not only requisite as an adjunct to food, but also for the animal economy; this fact is not to be lost sight of, and therefore I lay much stress on it, and in the next chapter we shall see that physiologically it holds no mean position amongst those other substances which are found in the human body.
There are a number of facts of physiological import, at which it is necessary to glance, and which are indissolubly connected with its medicinal and dietetic properties; and there are various others illustrative of the absolute necessity of salt, which are self-evident to those who think and observe, and which we will now proceed to lay before the reader.
In human blood, salt is a most important constituent; where there is disease, there is a diminution of salt, with corresponding nervous depression, and the individual experiences a want of power: if this want continues for any length of time, the health is gradually undermined; the blood loses its richness and is deprived of its vitalising property; various symptoms finally show themselves, and probably develop into some phenomena of a serious significance – all, indeed, indicative that the system is deficient of a most important essential in its economy. These symptoms may prognosticate the approach of various diseased conditions, partly owing to the habits, constitution, or surroundings of the patient. In all morbid conditions, and particularly in those which owe their origin to an unhealthy state of the blood, we may, to a considerable extent, be certain that there is a deficiency of the chloride of sodium. In proof of this, patients never, as a rule, object to salt; they actually relish it. Why? Because there is a deficiency, and nature intuitively excites the desire. We often find that patients refuse sugar; indeed the very mention of it produces a feeling of nausea and extreme disgust: with salt it is entirely different; they take it, and, in most cases, enjoy it in the same way that fever-stricken patients long for, and relish, a draught of cold water, if they are able to obtain it.
Were the human race once deprived of the chloride of sodium, even for a limited period of time, we should not only lose a natural healthful incentive for our food, but disease, with all her attendant miseries, would spread with such relentless impetuosity as would defy, and even paralyse, the efforts of the most skillful physician, the ingenuity of the surgeon, and the scientific improvements and hygienic precautions of the sanitarian.53 The strength and vigour of manhood would fade as if blasted by disease, food would act as a poison; the blood would not be replenished with the salt which it requires, and consequently our skins would soon be covered with corruption; our cattle would die, our crops would be nipped in the bud; the air would be full of offensive insects; the soil would become foul and barren, the sea a waste of stagnant waters; and all the beautiful productions of nature would wither and decay, and our glorious earth would degenerate into a hideous solitude, solely inhabited, very probably, by monsters horrible to behold, and more repulsive than those gigantic reptiles which once roamed by the dreary marshes of an incomplete world.
Those who take pleasure in decrying the inimitable works of nature, and affirm that they are provocative of evil, can only support their arguments by brazen assertions and subtle paralogisms.
Common salt is considered by most persons as a mere luxury, as if its use were only to gratify the taste, although it is essential to health and life, and is indeed as much an aliment or food as either bread or flesh. It is a constituent of most of our food and drinks, and nature has kindly furnished us with an appetite for it, though there are not a few who regard it quite in another light: that quadrupeds and birds (as I have before stated) should be fully alive to the vivifying properties of salt, and that mankind should be indifferent to, and in many instances totally ignorant of them, is somewhat curious and incomprehensible, but it is so.
Another strange fact is, that savage nations use it freely with but few exceptions: on the other hand, in civilised life there are a great number who never touch it; but these abstainers little think that they carry in their countenances visible signs of ill-health, and their impurity of skin indicates that at some future time disease, in some form or other, will cause them to regret, in more ways than one, that their short-sighted neglect has prepared a soil ready to receive the seeds of some fever, and other maladies more deadly and obstinate.
Cutaneous eruptions, so distressing to the patient, and so disgusting to an observer, flourish when they attack those who have abstained from the use of salt.
Everyone perspires or sweats: the indolent perspire, the laborious sweat. This distinction will be regarded as too fine by those who entertain the opinion that perspiration and sweat mean the same thing; this, however, is a great error; there is a marked difference between perspiring and sweating, as much difference, indeed, between these two processes of the elimination of refuse animal matter, as there is between walking and running. It is true the same laws of nature are brought into play; but one is a modification of the other. Those of a spare habit are seldom in a state of general diaphoresis, and are only so when the weather is sultry, or when they have taken a walk on a hot summer’s day. The stout or plethoric, on the contrary, sweat copiously, even on the slightest movement; and it is really a good thing for them that they do, for otherwise they would very likely be attacked with a fit of apoplexy, or would fall down from syncope; the former arising from the flow of too much blood to the brain, or from rupture of an artery; the latter resulting from an insufficient supply; or the blood owing to its circulating in an impure state, which is practically the case if there is a deficiency of salt, would generate, not what is generally considered disease, but a condition which would render the system prepared for the reception and development of morbific influences.
During perspiration the blood is deprived, in proportion as the diaphoresis continues, not only of the liquor-sanguinis, but of the chloride of sodium which it holds in solution. Though to a certain extent perspiration is an act of nature necessary for the continuance of health, yet, if it goes beyond a point which is consistent with an equalisation of the several secretions, the individual experiences a diminution or loss of power, and nervous exhaustion or irritability is the result. In natural diaphoresis the only way in which the system can recuperate itself is by quenching the thirst; for free perspiration is generally or almost invariably succeeded by a corresponding thirst, varying in intensity according to the peculiar idiosyncrasy of the individual.
Thin people do not perspire so copiously as those who are more stoutly built, therefore they do not lose so much and neither do they require so much fluid. Their blood, by reason of its retaining its liquor-sanguinis and its chloride of sodium, does not require salt as an aliment so freely as those who, owing to their profuse perspiration, are in constant want of it. Stout people, or those who have a superabundance of adipose tissue (for I must observe there is a great difference between stoutness and obesity, though in common parlance the two words are synonymous), require salt in a greater degree than thin people. Well-developed muscles covering a well-made frame, accompanied by a proper and due proportion of fat, constitute stoutness of a healthy standard; but small muscles covered with an overdue amount of fat, with an abdomen distended to an offensive size (which is so frequently seen), seem, in my opinion, to determine a habit of a Vitellian obesity, if I may so apply the name of that Roman epicure.
Owing to the fact that stout and fat people perspire freely and profusely, and to a much greater extent when undergoing fatigue, they must necessarily lose a great amount of salt; for as it is held in solution by the liquor-sanguinis, which passes through the pores of the skin in the form of sweat (the word perspiration is not sufficiently emphatic when we are speaking of stout and fat individuals), it must naturally pass out with it, and thus they experience thirst and a desire for salt; which desire is strongly indicative of a healthy state of the secretions. If there is no wish for salt, then we may conclude that disease in some form or other is lurking unsuspected in the system, ready to break out, either by an act of indiscretion, poisoned atmosphere, or because of a taint of an hereditary character. We may compare this condition of things to a barrel of gunpowder, ready on the application of the faintest spark to ignite, and spread confusion and death far and wide, with a fury proportionate to the amount of the inflammatory material. If these people do not take salt with their food they allow their blood to become impoverished and more unhealthy than it already is, and their constitutions materially suffer in consequence, their skins are ultimately affected, the complexion frequently becomes sallow, and appears discoloured, and in some severe cases we have that skin disease called acnæ, indicative of the poor and unwholesome state of the blood; they are affected with intestinal parasites, they do not digest their food, their breath has a most disagreeable odour, very unmistakable, and they are more or less out of health.
Those of a scrofulous habit require salt to a much greater extent than even the gross, because the blood of scrofulous or strumous persons does not possess its due proportion of salt; and the only way to make up for this deficiency is to use it freely, otherwise the system does not derive the support and nourishment from that source which vitalises the whole frame. We may justly infer that if the blood is deficient of a most important constituent the system must, as a matter of course, degenerate into a condition not only ready to receive disease, but into one which reduces the strength and undermines the nerve-power, and this in a scrofulous habit is fraught with serious consequences.
The chronic inflammation which attacks the joints in scrofula sometimes occurs, not so much from the unhealthy low state of the system, but rather from the impure condition of the blood, resulting from the partial absence of salt. This must be the case, because the sufferer experiences an increased vitality if salt is used more abundantly; the change of course is gradual, and therefore we must not expect to see one’s efforts immediately crowned with success. It is sometimes necessary to explain to scrofulous patients the unhealthiness of a persistent avoidance of salt, and to point out to them the benefits accruing from it, and also to insist upon their using it, because, owing to their ignorance of its operation and their unwise dislike, they look upon it in the light of a noxious compound.
I have frequently noticed (and I dare say others have observed the same thing) the disfiguring eruptions with which many people (and especially the young) of a scrofulous habit, and even some who are free from this taint, are afflicted about the face and neck. These pimples and blotches, when not caused by constipation, are generally accompanied by a swollen condition of the glands, which are sometimes acutely sensitive to the slightest pressure.
If we were to question them closely we should find that salt is to them an almost unknown article of diet, or distasteful to them, though no doubt it is, in some few instances, used but sparingly and seldom.
The blood, more or less, is always undergoing a change, even in health; the nitrogenised and non-nitrogenised substances are invariably variable, and at no two moments are the salts of the same proportion, its alkalescence always being in a constant state of variation. Notwithstanding our increased facilities for obtaining a better acquaintance with disease than formerly, the few facts which have been satisfactorily made out show us that as yet we have made but little progress as regards the morbid conditions of the human blood, and that a great deal remains to be accomplished before we are masters of the subject.
Amongst the chief diseases in which a pathognomonic condition of the blood has been discovered is the increase of the fibrine, which always takes place in inflammatory diseases, such as acute rheumatism and inflammation of the lungs; in low fevers it is diminished; it is also subject to variation in other diseases. In typhoid fever the diminution of salt and the increase of fibrine is very marked; and indeed in all inflammatory states of the system, especially of a sthenic type, the partial absence or variation of the amount of the chloride of sodium is a most important characteristic. No attention has, up to the present time, been given to the relation which the presence of the chloride of sodium in the blood bears to disease, at least not that I am aware of; and from what I have noticed it opens up a question which in time will be considered of some moment. As the chloride of sodium obviates the tendency of the fibrine to coagulate, and as its coagulation or solubility is quite dependent on its normal amount in the blood, it presents to us many varied points of interest, not only physiologically, but medicinally, though in this respect it has not yet been recognised as a curative agent.
Whenever the blood is impoverished we may be tolerably certain that salt is, in a greater or lesser degree, absent, or below the standard, and that it is variable.
Now in scrofula the blood is not only vitiated, but poor in the extreme, and there is a decrease of the fibrine; and that being the case, the constitution suffers in proportion, the affection showing itself in various ways, which unmistakably indicate the adynamic state of that fluid which permeates the whole frame.
Scrofula and her twin sister struma, for there is a difference, are low forms of chronic inflammatory cachexia, and are never entirely recovered from. We may justly term them systemic diseases originating local morbid phenomena, and which are always liable to give rise to obscure attacks of an apparently serious nature, but which are considerably modified if the treatment be simply hygienic, judicious, and practical; scrofula is always tedious and prolonged, and therefore, as I have said before, we must not anticipate that because salt is of a nature somewhat antidotal to it and its attendant evils, that its effects are to be observable instantaneously, or that any very remarkable results must necessarily be obtained. It is the reverse; the effects are slow in the extreme, but the benefit is permanent – that is, if the treatment adopted be calculated to restore to the blood that constituent so necessary for health.
This is easily explained – the unhealthiness of the system arising from mal-nutrition, owing to the blood being more or less deficient of a constituent which is necessary for the promotion of health, and being solely constitutional, it takes some time to make up for that deficiency, and to supply that which is lost. A disease of long standing, and of an hereditary character, is not speedily recovered from, particularly if the mischief is caused by, or is dependent upon, an impure state of the blood, and if there is not the normal amount of the chloride of sodium it must of necessity be corrupt.
Though salted provisions are apt to produce scurvy if continued for too long a time, yet in the case of those on board ship I do not think it arises exclusively from the salt itself, but by the unwholesome food upon which the toilers of the sea are obliged too often to subsist. The biscuits, which are of the coarsest kind, and sometimes worm-eaten, are certainly not calculated to keep up the stamina of the men; and the salt pork which they have three or four times a week is not exactly the food to promote a healthy condition of the blood; neither is the soup, which is little better than rice water, capable of even satisfying the cravings of hunger.
Besides, there is a very miserable custom, and which tends to ruin the health of our sailors, and that is the drink which is, I may say, encouraged on board ship, and officially served out to them daily, in the shape of rum, though of late they can have cocoa if they prefer. So habituated have they become to this that no captain would think of suggesting a diminution of the supply. Our sailors, poor fellows! will stand anything but the deprivation of their “grog;” they do not mind being crowded like beasts of burden in a close, stifling forecastle, eating coarse biscuits or unwholesome pickled pork, so long as they are duly supplied with their “grog” and allowed to go “ashore” and spend their contemptible pittance on poisonous compounds which burn their stomachs and sow the seeds of some deadly disease, and especially if they happen to be in the tropics.
All these inseparable accompaniments of nautical life are, without doubt, provocative of scurvy to a certain extent, and I am sure do not help to stave it off. If rum is taken on an empty stomach, day after day, as regularly as clockwork, we cannot expect that the men should be in a state of sound health, or that their blood should be pure; particularly if the voyage is long, the biscuits worm-eaten, the pickled pork of a questionable condition, sometimes even approaching putridity, and the rice-soup – upon which I shall abstain from passing any remarks, further than by saying that it is decidedly not of that quality tending to act as a substantial sustentation of men who work hard, and who are exposed to all weathers, both by night and by day. Indeed it is surprising that they can perform their duties as they do when we call to mind their irregularities, their daily use of spirits, and their periodical alcoholic indulgences when ashore, combined with their abominable diet on board ship.