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BORACIC ACID 



Cryptomorphite is a bydrated borato of lime and soda, with 58'5 por cent, of 

 boraoio acid, closely related to Ulexite. It has been found in Nevada, 



Lardarellite is a borato of ammonia found in the lagoons of Tuscany, and named 

 after the late Count Lardarel the founder of the Tuscan boracic acid industry. 



Lagonite is an earthy borato of peroxide of iron, also found in these lagoons. 



In addition to the species noticed above, in which boracic acid forms a main 

 constituent, there are several minerals which contain this acid in subordinate quantity. 

 Thus, boracic acid is present in Danburite to the extent of about 28 per cent. ; in 

 Datolite to about 22 per cent. ; in Tourmaline in variable proportions up to 12 per 

 cent. ; and in Axinite it is present in quantity ranging from 2 to 5 per cent. But of 

 all the boracic minerals it is only the boratos of soda, lime, and magnesia, which 

 have hitherto been found in sufficient abundance to be economically employed in the 

 preparation of boracic acid and the alkaline borates. 



The great supply of boracic acid, however, is derived from the boracic acid 

 lagoons of Tuscany. Before the discovery of this acid, in the time of the Grand- 

 Duke Leopold I., by the chemist Hoffer, the fetid odour developed by the sulphuretted 

 hydrogen gas and the disruptions of the ground occasioned by the appearance of new 

 soffioni, or vents of vapour, had made the natives regard them as a diabolical scourge, 

 which they sought to remove by priestly exorcisms ; but since science has explained 

 the phenomena, the fumaochi have become a great boon to the district, and a source 

 of public prosperity. 



The hot vapours of the soffioni consist of a mixture of permanent gases, 

 condensible vapours, and mechanically-suspended solid particles. Among the usual 

 constituents may be mentioned carbonic acid gas, nitrogen, oxygen, sulphuretted 

 hydrogen, watery vapour, ammonia, sulphate of ammonia, hydrochloric acid, organic 

 matter, and boracic acid. To collect this boracic acid, which is never present in more 

 than very minute quantity, the soffioni are enclosed by low walls of coarse masonry, 

 or brick-work, glazed on the inside, and forming a series of circular basins, the 

 diameter and depth of which vary greatly in different works. The larger basins may 



enclose several distinct vents. A series of these circular basins is arranged in 

 terraces on the side of a hill, as represented in fig. 170. A small stream of water, 

 from an adjacent spring, is introduced into the uppermost basin A D, thus forming a 

 small pool or artificial lagoon. By the escape of the hot vapours rising from below, 



the water of this lagoon becomes more or loss agitated and gradually heated, and at 

 the same time impregnated with the boracic acid. After standing for 24 hours in the 



