Analyses of the Waters of The Hot Springs of Arkansas
Geological Sketch of Hot Springs, Arkansas
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One of the most important groups of mineral waters are the alkaline waters, which are characterized by the presence, in predominating quantities, of one or more of the alkaline or alkaline earth carbonates or bicarbonates. These are the carbonates or bicarbonates of sodium, potassium, lithium, calcium, and magnesium. In case iron is present in large quantities as the bicarbonate we have a water belonging to the chalybeate class. Since these waters are alkaline they are excellent remedies in cases of sour stomach and in sick headaches which arise from acid dyspepsia. They act very markedly on the mucous membranes, increasing the flow of the gastric juice and other digestive fluids, and are consequently of use in many cases of indigestion. In conjunction with the sulphated salines they give excellent results when used in the treatment of catarrhal conditions of the stomach and intestines. Such waters correct acidity of the urine, markedly increase the flow of urine and help to dissolve uric acid deposits. They are therefore of value in cases of rheumatism and gout.

Sodium carbonate and bicarbonate.—Sodium carbonate or bicarbonate appears as a normal constituent of the blood, lymph, and nearly all secretions of the mucous membrane. Where conditions arise that cause these fluids to become acid, waters containing carbonate or bicarbonate of soda are of value in counteracting the effect. Waters containing either of these substances have been used with excellent effect in the treatment of acid dyspepsia and diabetes.

Potassium carbonate and bicarbonate.—Potassium carbonate and bicarbonate are readily soluble in water. The bicarbonate is the one usually present in mineral waters. The properties of this salt are very much the same as those of sodium bicarbonate. It increases the flow of urine and corrects acidity of the bodily fluids.

Lithium carbonate and bicarbonate.—Lithium carbonate is very sparingly soluble in water, while the bicarbonate is quite soluble. It is in the latter form that lithium is most often reported in mineral waters. This compound is most frequently used in cases of rheumatism and gout, where it forms a very soluble urate which is easily eliminated from the system.

Magnesium carbonate and bicarbonate.—Magnesium carbonate and bicarbonate are mild laxatives and are perhaps the best of all the carbonates and bicarbonates in correcting an acid condition of the stomach, and curing sick headache caused by constipation.

Calcium carbonate and bicarbonate.—Calcium is usually present in waters as the bicarbonate. Both of these compounds are quite different in their effects from the other carbonates and bicarbonates mentioned. While the others are evacuant and promote secretions, the calcium compounds constipate and decrease the secretions. Very obstinate cases of chronic diarrhea have often been cured by a sojourn at a spring rich in calcium bicarbonate.

Ferrous and manganous bicarbonates.—Neither iron nor manganese ever occur in mineral waters as the carbonate, but usually as the bicarbonate. Both of these compounds have practically the same effect. When taken internally, they are dissolved by the gastric juice and taken into the blood. They increase the appetite and the number of red blood corpuscles. It will thus be seen that such waters give excellent results when used as a tonic or in cases of anaemia. Too long continued use of waters rich in bicarbonate of iron or manganese result in constipation and derangement of the digestion.


Chlorine occurs in waters as chlorides, in combination most frequently with sodium, potassium, or lithium, and sometimes with calcium, magnesium or iron. The chlorides form the basis of that large group of mineral waters, the muriated salines.

Sodium chloride.—Sodium chloride occurs in almost all mineral springs to some slight extent, but in the muriated saline waters it occurs in large quantities as a predominating constituent. Waters containing large quantities of this substance are chiefly used in giving baths, which increase the action of the skin, and by absorption through the pores serve as a genuine tonic. Taken internally the flow of the digestive fluids is promoted and the appetite increased. Putrefactive changes in the intestines are also prevented. In large doses sodium chloride increases the flow of urine and the amount of urea present in the same.

Potassium chloride.—Potassium chloride has very much the same effect on the human system as does sodium chloride.

Lithium chloride.—Lithium chloride has practically the same effect as lithium carbonate and bicarbonate mentioned above.

Magnesium chloride.—Magnesium chloride is often used medicinally as a cathartic and to increase the flow of bile.

Calcium chloride.—Calcium chloride occurs in a number of muriated saline springs. It is used in cases of general debility as a tonic. It increases the flow of urine and perspiration and waters containing it are used in the treatment of scrofulous diseases and eczema.

Ferrous chloride.—The occurrence of ferrous chloride in mineral waters is rather rare. When present, however, it acts as a tonic and in general has the same properties as ferrous bicarbonate, already mentioned.

Ammonium chloride.—When used internally, ammonium chloride has the stimulating effect of ammonia. It is used in nervous cases as ovaralgia, sciatica, and other neuralgic disorders. In congestion of the liver its use has been beneficial. Externally it is used as a wash for ulcers and sores. It, however, seldom occurs in springs in quantities large enough to be of any value.


Sulphates are frequently found in mineral waters, and when present in large quantities give rise to that large class, the sulphated salines.

Sodium and magnesium sulphates.—Sodium and magnesium sulphates, or Glauber and Epsom salts, respectively, in small doses act as a laxative, in large doses as a cathartic. They are both valuable in increasing the flow of the intestinal fluids and in increasing the flow of urine, accompanied by an increased elimination of urea. Waters containing these salts are of great service in eliminating syphilitic, scrofulous, and malarial poisons from the system, and in eliminating mercury and other metallic poisons. Persons suffering from obesity, derangement of the liver, and Bright's disease are perhaps the most benefited by this class, of waters. It must be borne in mind that such waters should be used with great care by the feeble and anaemic.

Potassium sulphate.—Potassium sulphate is frequently present in mineral waters, but in smaller quantities than the magnesium and sodium salts. Its action is practically the same as that of the other two sulphates mentioned above.

Calcium sulphate.—Calcium sulphate occurs in a great many mineral waters, and is the component that gives to them the property of permanent hardness. It is not used medicinally.

Iron and aluminum sulphates.—Iron and aluminum sulphates are usually found associated with each other in mineral waters. They are both powerful astringents. The waters containing iron sulphate are also used as tonics, but this is not nearly as good a form in which to give the iron as is the bicarbonate. Because of their astringent action, waters containing these two substances have been used with success in treating locally inflamed parts of the mucous membranes and ulcers on the outside of the body.


The iodides are usually reported in mineral waters as the potassium or sodium salt. They are alterative in effect and are consequently used in the treatment of scrofula, rheumatism, and syphilis. While drinking waters containing iodides the flow of urine is very much increased and mercurial and other metallic poisons are rapidly eliminated from the system.


Bromides act as alteratives in much the same way as iodides but to not so marked an extent. They also act as sedatives.


Phosphates in mineral waters are usually reported in one of three forms, viz, sodium, iron, or calcium phosphate. The sodium phosphate acts as a mild laxative, the iron phosphate as a tonic, and the calcium phosphate as a medicine in those conditions of the body where lime salts are deficient, as rickets, etc.


Boric acid is not a very common constituent of natural waters but is found as the sodium salt in springs of southern California in large amounts. Applied as a douche in catarrhal conditions of the uterus it is of value.


Any nitric acid that may appear in a water is usually reported as sodium nitrate. This compound does not usually occur in waters to a marked extent unless they are contaminated. When present in large enough amounts it increases the flow of urine and acts as a purgative.


Silica appears in mineral waters both as free silica and as silicates. The medicinal value of silica has not been thoroughly investigated.


The gases that usually occur in water are nitrogen, oxygen, carbon dioxide, and hydrogen sulphide.

Nitrogen and oxygen.—Nitrogen and oxygen are present in all waters that have come in contact with the air. On account of the limited solubility of both they can not occur in waters in very large quantities. Neither of them when present in waters has any medicinal value.

Carbon dioxide.—Carbon dioxide is present in all natural waters to some extent, but in some springs the amount is very large, thus giving rise to that large class of carbonated waters of which the Saratoga springs furnish a good example. Such waters are extremely palatable, and large quantities can be drunk without the full feeling which so often follows copious drinking of water. In moderate quantities such waters increase the flow of the saliva, promote digestion, and tend to increase the flow of urine. Obstinate cases of nausea can be often relieved by the use of small quantities of highly carbonated waters.

Hydrogen sulphide.—Hydrogen sulphide is present in many natural waters, giving to them the odor of decayed eggs, and forming that large class, the sulphureted waters. When such waters are taken internally they act as an alterative, and are consequently of value in the treatment of syphilitic diseases. They increase the activity of the intestines, kidneys, and sweat glands, so are of use in the treatment of rheumatism and gout. Excellent results have been obtained when these waters were used in treating many skin diseases and malaria.

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Last Updated: 22-Dec-2011