Salt (chemistry)

“ By repeating the operation and fusing the salt (when adhering hydrochloric acid is volatilised) a pure salt is obtained, which is again crystallised from its solution by evaporation. [9]
Pure sodium chloride, in well-defined crystals (slowly deposited at the bottom of the liquid) or in compact masses (in which form rock salt is sometimes met with) , is a colourless and transparent substance resembling, but more brittle and less hard than, glass. [10] Common salt always crystallises in the cubic system, most frequently in cubes, and more rarely in octahedra. ”

“ Enormous quantities of salt are therefore produced each year. Small quantities are essential to the life of man and animals. Pure salt does not absorb moisture; the fact that ordinary salt becomes moist in air is not due to a property of the salt, but to impurities commonly occurring in it, especially calcium and magnesium chlorides.
Sodium sulphate (Glauber's salt) (Na2SO4·10H2O) . This salt is prepared by the action of sulphuric acid upon sodium chloride, hydrochloric acid being formed at the same time:
2NaCl + H2SO4 = Na2SO4 + 2HCl. ”

“ Is it not a blessing to know that nature has munificently provided a means whereby these distressing evils may be checked and definitely eradicated by a daily use of such an enemy to, and destroyer of, disease as the chloride of sodium, universally known as common salt? ”

“ Physiology has been a boon to humanity and an inexhaustible field of research to the scientific.
In a chemical point of view there is no more important mineral constituent in the human body than the chloride of sodium, for it occurs nearly in every part of the system, both solid and fluid, in close and intimate relation with the organic compounds, and it materially influences their chemical and physical properties; for instance, the albumen partly owes its solubility to the presence of salt, the quantity of which causes the differences which it presents as regards its coagulation ”

“ SALTS Of all salts found in the body, the most abundant and valuable is sodium chloride (NaCl) , common salt; it exists in all tissues, secretions, and fluids of the body, with the exception of enamel of the teeth. The amount found in food is not always sufficient; therefore salt is used as a condiment. It assists digestion, inasmuch as it furnishes chlorine for hydrochloric acid found in gastric juice. ”

“ Simple and harmless as it is, while it exists as a compound of the original elements, when separated into those elements they are each very unpleasant and even dangerous substances to handle. Salt is one of the most common substances in nature. It is found in many parts of the world in solid beds, and is one of the prominent constituents of sea-water.
Salt is a compound of chlorine and a metal called sodium. Sodium in its pure state has a strong affinity for oxygen, so much so that when a lump of it is thrown into water it takes fire and burns violently with a yellow flame. ”

“ Even at the highest temperatures, heat cannot effect the decomposition of common salt. At a red heat, pure sodic chloride melts and becomes liquid, and if cooled again, a solid crystalline mass is formed. Ordinary salt fuses at a lower temperature and volatilizes when heated in an open vessel. ”

“ Salt is rarely if ever ob- tained pure. The chief impurities in rock salt are sulphate of lime, oxide of iron, and clay; but besides these the chlorides of potassium, calcium, and magnesium, the sulphates of soda and magnesia, and bituminous matters are occasionally met with, and some varieties are even colored by the presence of infusoria. In salt made from sea water, the salts of magnesia with a little sulphate of lime are the principal impurities. All the varieties of salt occasionally contain minute quantities of bromides and iodides. ”

“ As you walk along on top of them, you can smell a faint violet perfume from the salt. Thatch is put over the cones to protect them from the rain, and there they stand till some of the impurities drain away. This salt is not perfectly white, [Pg 98] because the workmen cannot help scraping up a little of the gray or reddish clay with it. Most of it is sold as it is, nevertheless, for many people have an absurd notion that the darker it is the purer it is. For those who wish to buy white salt it is sent to a refinery to be washed with pure water, then boiled down and dried. ”

“ When pure, this salt is colourless and odourless; it forms cubic or octahedral crystals, which are anhydrous; it is freely soluble in water and in boiling alcohol, but most of it separates from the latter as the solution cools; it is fusible; and undergoes no change, even at a full red heat, in close vessels; it exhibits an alkaline reaction; when exposed to the atmosphere, it absorbs moisture, and acquires the smell of hydrocyanic acid. If it effervesces with acids, it contains carbonate of potassium, and if it be yellow it contains iron. ”

“ By this operation common salt is got from seawater and salt springs, both artificially, and, in hot countries, by the natural heat of the sun. When the water is no more than is just sufficient to dissolve the salt, it is called a saturated solution, and on evaporating the water further, the salt begins to separate, forming little regular masses called crystals. Sugar may be made in like manner to form crystals, and then it is sugar-candy. ”

“ In some countries remote from the sea, which are devoid of salt-mines, and where the water is not impregnated with it, the inhabitants, aware of its usefulness, have a method of extracting it from the ashes of vegetables. This fact would certainly seem to indicate that salt has been used by various nations, as if mankind had an intuitive knowledge of the benefits arising from the use of salt, and that consequently, if there were no lakes containing it, or mountains from which they could procure it, they were determined to obtain it if even by artificial means. ”

“ Use of Salt.—Among other follies of the day, some indiscreet persons are objecting to the use of salt, and propose to do without it. Nothing could be more absurd. Common salt is the most widely-distributed substance in the body; it exists in every fluid and in every solid; and not only is it everywhere present, but in almost every part it constitutes the largest portion of the ash when any tissue is burned. In particular, it is a constant constituent of the blood, and it maintains in it a proportion that is almost wholly independent of the quantity that is consumed with the food. ”

“ Our understanding of salt has been broadened and deepened. Salt is a much more complex thing to us now than it was before. Instead of simplifying salt by reducing it to its elements, we have greatly complicated it. But notice this particularly: The new knowledge has not enhanced by one jot our knowledge of the physical properties of salt. There is nothing whatever in the properties of the sodium or the chlorine that gives us any clue to the properties of the salt. ”

“ Common salt is a combination of the metal sodium and the gas chlorine. There are many places, of which Cheshire is a notable example, where vast quantities of this salt lie buried in the earth.
Fortunately it is very easily dissolved in water so that if wells be sunk in a salt district the water pumped from them will have much salt in solution in it. This is how the underground deposits are tapped. It is not necessary for men to go down as they do after coal, for the water excavates the salt and brings it to the surface. ”

“ When, therefore, common salt becomes damp by mere exposure to the air, it is to be inferred that it contains impurities which, as they possess a very bitter taste, would, if mixed with butter, confer a bad flavor upon it. The impurities of salt may be almost completely removed by placing about a stone weight of it in any convenient vessel, pouring over it a quart of boiling water, and mixing thoroughly the fluid and solid. ”

“ One-tenth of one gram is an amount naturally found in food, and that should be enough; human beings should not be any different from wild animals. The salt refining factories and the salt retailers can go belly up any time they like. It is idiotic to believe that people must ingest the same proportion of salt as is contained in the blood. One should consider that 0.1 gram of salt has accumulated in the blood. ”

“ More than half the ten ounces of salts consist of it alone, which will make you understand better than before, what I explained with reference to the stomach; that is, why we put salt in our food. The porter above is quite up to his business when he asks everyone who enters to produce his little bit of salt. It is an attention which the blood appreciates very highly, although table-salt is of no great use to him in his building operations ”

“ 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. ”

“ Common Salt is a chloride of sodium, and exerts an extraordinary influence on animal as well as vegetable life. All marine animals and plants seem to have their existence determined by this substance. It enters into the composition of the human body, and all over the world man uses it, when he can obtain it, in its mineral form, as an addition to his food. ”

“ In each gallon of river or rain water dissolve about six ounces of sea-salt, either by stirring it or suspending it in the water in a linen or muslin bag. It dissolves as readily in cold as in hot water. Sea-salt is produced by evaporation of sea-water. Common salt is sometimes supplied in place of it; but the genuine sea-salt, manufactured by well-known firms, which can be procured of any grocer or of most chemists, is specially prepared to enable persons to have a salt-water bath at home. ”

“ Salt is found in greater or less quantities in almost every substance on earth, but the waters of the sea appear to have been its first great magazine. It is found there dissolved in certain proportions, and two purposes are thus served, namely, the preservation of that vast body of waters, which otherwise, from the innumerable objects of animal and vegetable life within it, would become an insupportable mass of corruption, and the supplying of a large proportion of the salt we require in our food, and for other purposes. ”

“ THE BEGINNINGS OF THE SALT INDUSTRY Salt, being existent in all animal and vegetable life, is coeval with life itself; it was present in the first herbage which gave nourishment to the first beast that, in its turn, became food for the first omnivorous man. In the beginning, man consumed the saline essences that were required to preserve his body in health, in the form of sodium chloride, which he absorbed in the uncooked flesh of animals, birds, and fishes, and in raw green-foods. ”

“ Now, of course, it is true that anyone who knows the principle of the nomenclature of salts, to which, we suppose, Hugh Miller refers, can tell a good deal about a [Pg 182] salt from the name of it, say, nitrate of potassium, KNO3, but it would be impossible to invent a systematic nomenclature of which this would not be true. ”

“ The hydrochloric acid of the gastric juice, which is so bountifully secreted by the glands of the stomach, of course drains the whole system of its salt, and especially does it draw the chloride of sodium from the blood, which contains 3·6 in 1000, being held in solution by the liquor-sanguinis.
Animal or nitrogenous food contains only a minimum of salt, which chiefly exists in the muscular tissue, its principal constituents being albumen and fibrine ”

“ A very serious difficulty presents itself in the great thickness of many strata of salt; which, if regarded as the solid residuum of sea-water, must have necessarily required a proportionate volume of water, unless the seas of those distant periods contained a larger amount of saline ingredients than they do at the present time: an inference for which there are no reasonable grounds.
Wherever there are deposits of the chloride of sodium, they are almost always accompanied with layers and intercalations of gypsum ”

“ Common salt is deposited in large quantities in different parts of the earth. Since salt is readily soluble in water, many streams pick up large quantities of it, and as all water courses ultimately find their way to the ocean, the latter becomes a repository for salt with which the earth-water is laden. ”

“ Be not worth one's salt, not to deserve even the salt that gives relish to one's food; Bronzing salt, used in burning gun-barrels; Epsom salts, magnesium sulphate, a cathartic; Essential salts, those produced from the juices of plants by crystallisation; Glauber's salt, or Horse salts, a well-known cathartic, used in woollen dyeing; Lay salt on the tail of, to catch; Neutral salt, a salt in which the acid and the base neutralise each other; Rochelle salt, sodium potassium tartrate, a laxative; Spirits of salt, the old name for muriatic or hydrochloric acid ”