BORACIC ACID. 
337 
that water gains access to immense masses of sulphuret of boron con- 
tained in the interior of the earth. By the mutual reaction of these sub- 
stances, great heat, boracic acid, and sulphuretted hydrogen, would be 
evolved. The latter taking fire would produce water, sulphur, and sul- 
phurous acid. (Dumas, Traite de C/timie, t. i. p. 380. Paris, 1828.) In 
consequence of being found at Sasso, native boracic acid has obtained the 
name of Sassoline. 
J3. Combined wilh bases. — Boracic acid is found native combined with 
soda (forming Tinea/,) and with magnesia (constituting Boracile.) It is 
also found in the minerals called Datholite, Boiryolite, Schorl, Apyrite, and 
Axynite. 
Process of Manufacture. — Boracic acid is obtained in 
Tuscany in the following manner: — " Round the more con- 
siderable fissures a circular basin is dug, about four feet deep, 
and usually three or four yards across. These basins, which 
are called lagoni, being situated at different levels, the water 
of a rivulet is admitted into them, which, mixing with the 
black mud at the bottom, is made to boil up violently by the 
issues of vapour within its circuit. The water is generally 
confined in each basin for twelve [twenty-four, Payeri] hours 
at a time, during which period it becomes saturated to a cer- 
tain extent with acid from the steam which has passed through 
it. It is then drawn off from the higher basin to one beneath 
it, where it remains an equal length of time, till at length it 
reaches a building at the bottom of the hill, in which the pro- 
cess of evaporation is conducted." Here it enters a reservoir 
or cistern, where it is allowed to repose till it has deposited 
the mud which it held in suspension. Having cleared itself 
of impurities, the water is then drawn off from the cistern into 
flat leaden pans, under which some of the natural steam is 
conducted by brick drains about two feet under ground, and 
by this heat is evaporated. This process requires about sixty 
hours, the water passing successively from the pans at the 
upper extremity into others at the centre, and from thence 
into others at the lower extremity of the building, by means 
of leaden siphons. 
vol. i., Oxford, 1837; Dr. Bowring, On the Boracic Acid Lagoons of Tus- 
cany, in The Lond. and Edinb. Philosoph. Magazine, vol. xv. p. 21. Lond. 
1839; and Payen, Jinn. Vhim. et Phys. 1841. 
