Chapter XVIII: Boron

The white substance called borax has long been known to exist as a solid deposit in the earth of many parts of the ancient East. But its uses have increased a thousand fold as the result of the modern discovery of new and far more abundant sources of it. Thus in the manufacture of porcelain and in other of the industrial arts, and as a remedial agency in medicine, borax has now come to be an important and truly useful substance to mankind.

The knowledge of its composition is referable to a very recent date; only in the present century its character as a true chemical salt was fully made out. Borax is now recognized as sodic borate, which usually exists in a form holding ten molecules of water of crystallization; accordingly the chemical formula is Na₂B₄O₇ + 10 H₂O. From this it appears that, in addition to the well-known substances sodium and oxygen, borax contains a special and peculiar element called boron—a name evidently derived from borax. Again, being a salt, the substance must be viewed as containing an acid—or more properly speaking, the representative of an acid. That this is indeed the fact may be readily proved. If borax is dissolved in water in such a way as to form a concentrated solution, then, upon addition of chlorohydric acid, a solid substance separates out in pearly flakes; this upon subsequent examination is found to be an acid. This solid acid has received the name boric acid, and it may be represented by the formula H₃BO₃.

Sources of Borax in Nature.

For a long time the only known source of borax was the natural crusts of this substance found principally in the ground in certain parts of Asia. At the present day, however, borax is obtained from Borax Lake, in California, in very large quantities. In fact the commercial needs of the United States for this substance, are readily supplied from borax found within its own borders. The most interesting and important step in connection with the preparation of borax dates back to about the year 1776, when the fact was made public that certain lagoons in Tuscany contained boric acid in their water. It was not until about the year 1828, however, that the manufacture of boric acid from this source was successful upon a large scale. In some of the Tuscan valleys there are volcanic crevices in the earth, called _suffioni_. From them steam escapes charged with certain compounds of boron. When this steam is brought in contact with water, boric acid is liberated in the water. The method of securing the acid is as follows: A ring of masonry is built in a suitable place and so as to include several suffioni. Sometimes new suffioni are artificially bored within this ring. Into the basin so produced, water from some convenient spring is conducted. The steam from the suffioni passing into the water, produces boric acid there. When the water is sufficiently charged, it is made to flow as a gentle cascade over a long series of shallow pans. The liquid readily evaporates from these pans for under them also, steam from suffioni is turned. It is indeed this last mentioned step in the manufacture, that became the turning point which has lead to its successful prosecution. The great cost of fuel for artificially evaporating the acid liquors, rendered unprofitable the earlier attempts to utilize this source of boric acid. A French gentleman, M. Larderel, suggested the use of steam from suffioni for the evaporation of the liquids produced, and the process was so successful that he quickly derived a colossal fortune from its employment. At the same time he enriched the territory that was previously not only desert and unproductive, but also was looked upon by the inhabitants with superstitious dread and as little better than the gate of the infernal regions. As a result of these inventions, a barren and unfrequented territory has been changed to a seat of thriving and beneficial industry. Finally, it is interesting to note that for his services in developing the boric acid industry M. Larderel was created Count of Monte-Cerboli by the Grand Duke of Tuscany.

READING REFERENCES.

Boric Acid, Manufacture of, etc.
=Payen.=—Annales de Chimie et de Physique. 3 Sér. i, 247;
ii, 322.
=Dieulafait=, L.—_loc. cit._ 5 Sér. xii, 318; xxv, 145.

Borax Lagoons of Tuscany.
=Harper’s= Magazine. i, 397.