Page:Littell's Living Age - Volume 133.djvu/644

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from the ground has a temperature of about 190° Fahr., there are deposits of boronatrocalcite, extending over considerable areas. Here, as far as the eye can reach, nothing is seen but barren mountains, formed of a black, porous lava; while the valleys are covered by an efflorescence of a mixture of common salt and sulphate and carbonate of sodium. In other cases the sands of these mountain valleys contain deposits of more or less pure boronatrocalcite.

Geysers and hot springs are numerous in the whole of this district, and from the number of extinct geyser vents still visible, they were, probably, at one time much more numerous than at present.

The analysis of an average sample of the boracic material from Nevada afforded Mr. Loew the following results: —

Boronatrocalcite 22.13   
Chloride of sodium 2.80   
Sulphate of sodium 2.62   
Sulphate of calcium 6.17   
Carbonate of calcium 3.01   
Carbonate of magnesium .79   
Clay 19.70   
Quartzose sand 26.03   
Water 15.04   
Traces of potash, iodine, and loss 1.71   

The purification of crude borax (tincal) is effected by a simple re-crystallization, but the preparation of marketable borax from boronatrocalcite is attended with considerable difficulty, more particularly as the appliances available in the remote deserts in which it occurs are of the most primitive and limited description.

When boronatrocalcite is moderately pure, it is first ground and subsequently dissolved in water, with the addition of an amount of carbonate of sodium sufficient to effect the decomposition of the calcic carbonate present.

The solution is subsequently heated, and the carbonate of calcium allowed to subside, when the liquor is drawn off, and, after concentration, borax is obtained by crystallization.

Unfortunately, this mineral often contains notable quantities of gypsum, which transforms an equivalent amount of carbonate of sodium into Glauber salt, a relatively valueless product. This salt is also frequently present in the material operated upon, and thus materially adds to the difficulty of treatment. In order to avoid these difficulties, it has been proposed to treat native boronatrocalcite with sufficient sulphuric acid to transform the whole of the carbonate of calcium into gypsum, and to liberate boric acid, to be subsequently saturated by carbonate of sodium. Boronatrocalcite has also been treated with excess of hydrochloric acid, in order to obtain crystallized boric acid, but neither of these processes has hitherto afforded satisfactory commercial results.

The comparatively recent discovery of large quantities of this substance in Nevada will, no doubt, eventually to some extent, affect the Tuscan producers of boric acid; but the fact that crude boronatrocalcite varies considerably in its composition, and that it is found in situations in which its local treatment would be almost impossible, has hitherto prevented this mineral from being extensively employed as a source of commercial borax.

From The Spectator.


Mr. Gladstone, in replying for "the interests of literature" at the Royal Academy, intimated that we must not expect to see soon again so great a literary period as that which commenced with the peace of 1815; but beyond intimating that the immediate future was likely to be an age of research rather than one of expression, he gave no hint of the reasons which are likely, in his opinion, to prevent the present day from becoming a day of great literary splendor. Yet one reason, at all events, is conspicuous why this should not be so, and one, we fear, which is not likely to diminish, but rather to increase in influence, — we mean, and our reason will only seem paradoxical to those who have not thought much on these subjects, the very great and increasing facilities for literary expression, which prevent anything like large reserves of feeling and thought from accumulating till they acquire sufficient mass to produce great individual effects. Yet almost every great literary period in the world has been one following a long period of repression, and consequently of accumulation. When Athens first opened the sluices of literary life and power, the world awoke almost for the first time to the conception of literary freedom, and to the full power of human thought and language. The revival of learning was a period of similar awakening after a long pressure of the yoke of ecclesiastical restraint. The glory of Elizabethan litera-

  1. Moniteur Scientifique, 1876, p. 1230.