Collier's New Encyclopedia

A complete general encyclopedia of 1921 — the world as it was understood just after the Great War, from Aachen to Zwingli, across twelve volumes and six thousand pages.

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Rochelle Salt

the popular name of the bitartrate of soda and potash (KNaC4H4O6 + 4H2O), this salt having been discovered in 1672 by a Rochelle apothecary named Seignette. It occurs, when pure, in colorless transparent prisms, generally eight-sided; and in taste it resembles common salt. It is prepared by neutralizing cream of tartar (bitartrate of potash) with carbonate of soda. After a neutral solution has been obtained, it is boiled and filtered, and the resulting fluid is concentrated till a pellicle forms on the surface, when it is set aside to crystallize. This salt is a mild and efficient laxative, and is less disagreeable to the taste than most of the saline purgatives.

ROCHES MOUTONNÉES, smooth, rounded hummocky bosses and undulating surfaces of rock, of common occurrence in regions which have been overflowed by glacier ice. The name is that used by the Swiss peasants-the bare rounded rocks of a valley bottom when seen from above having a fanciful resemblance to a flock of sheep lying down.

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