ON THE BORACIC ACID LAGOONS OF TUSCANY. 41 
The borax lagoons have been brought to their present profit- 
able action within a few years. Scattered over an extensive 
district, they are become the property of an active individual? 
M. Larderel, to whom they are a source of wealth, more valua- 
ble perhaps, and certainly less capricious, than any mine of 
silver that Mexico or Peru possesses. The process of manu- 
facture is simple, and is effected by those instruments which 
the localities themselves present. The soffioni, or vapors, 
break violently forth in different parts of the mountain re- 
cesses. They only produce boracic acid when they burst with a 
fierce explosion. In these spots artificial lagoons are formed by 
the introduction of the mountain streams. The hot vapor 
keeps the water perpetually in boiling ebullition ; and after it 
has received its impregnation during twenty-four hours at the 
most elevated lagoon, the contents are allowed to descend to 
the second lagoon, where a second impregnation takes place, 
and then to a third, and so forth, till it reaches the lowest re- 
ceptacle ; and having thus passed through from six to eight 
lagoons, it has gathered one-half per cent, of the boracic acid. 
It is then transferred to the reservoirs, from whence, after a 
few hours rest, it is conveyed to the evaporating pans, where 
the hot vapor concentrates the strength of the acid by pas- 
sing under shallow leaden vessels from the boiling fountains 
above, which is quite at a heat of SO°R.,* and is discharged at 
a heat of 60°.t There are from ten to twenty pans, in each of 
which the concentration becomes greater at every descent, till 
it passes to the crystallizing vessels, from whence it is carried 
to the drying rooms, where, after two or three hours, it be- 
comes ready to be packed for exportation. 
The number of establishments is nine.J The whole amount 
produced varies from 7000 to 8000 pounds (of 12 ounces) per 
day. The produce does not appear susceptible of much ex- 
tension, as the whole of the water is turned to account ; the 
*The boiling point, f 167° Farenheit. 
:j:The principal are Monte Cerboli, Monte Rotondo, Susso, Serazzano, 
and Castelnuovo. 
VOL. vi. — no. i. 
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