REMARKS.

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by an assemblage of lines, crossing each other in infinite direc-tions, present an aggregate of cells or cavities, most commonlyso perfectly closed that the vessel may be inverted without theescape of the smallest drop of the lixivium, though sometimesincluded to the amount of an ounce or two. For this reason, itis necessary to break this fine crystallization, that the fluid mayrun off. The crystals present in their regular formation rectan-gular tetragonal blades, which as they contain little water ofcrystallization, produce a considerable degree of heat when dis-solved in water.

By exposing such alcaline crystals to a red heat in a silver cru-cible, they become fused ; and, after cooling, afford a mass aswhite as snow, extremely caustic and deliquescent.

As the crystals and the lixivium, during the length of timerequired to drain the salt, may frequently become charged witha portion of carbonic acid, it is advisable, in order to avoid thisinconvenience as much as possible, that the lixivium, as soon asit is brought to the requisite point of concentration, should bepoured into a narrow-necked bottle, and well closed therein tocrystallize. After the crystals are formed, the bottle is to bereversed without opening, and kept at a temperature rather warmuntil the crystals are well dried. During the winter, the liquor,after the first crystallization, continues to crystallize withoutbeing submitted to a new evaporation, provided only that it beexposed to a temperature somewhat colder than that wherein thefirst crystals were formed.