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BORACIC ACID. 
Boracic Acid Lagoons of Tuscany. 
A, B, C, D. Lagoons, — The vapours enter at the bottom, and escape 
through the water into the air. When the water in the upper 
lagoon, A, is sufficiently charged with acid, it is allowed to 
run through the tube, o, into the lower lagoon, B. In this way 
it passes successively from B to C, from C to D, and from D 
into the reservoir, E. 
E, F. Reservoirs or Cisterns. — In these the solution is allowed to rest, 
and deposite mechanical impurities. By the removal of the 
upper plug, p, the solution escapes into the upper evaporating 
pan, G. 
G, G. Leaden Evaporating Pans. — They are supported by rafters, and 
are heated by the aqueous vapours, which enter at H and are 
confined in drains. The acid solution is conveyed from one pan 
to another by means of leaden siphons, ii. 
