Volume 1

The chemical works of Caspar Neumann ... / abridged and methodized. With large additions, containing the later discoveries and improvements made in chemistry and the arts depending thereon by William Lewis.

  • Neumann, Caspar, 1683-1737.
Date:
1773
Catalogue details

Licence: Public Domain Mark

Credit: The chemical works of Caspar Neumann ... / abridged and methodized. With large additions, containing the later discoveries and improvements made in chemistry and the arts depending thereon by William Lewis. Source: Wellcome Collection.

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    Essen- land heat till about one half is wafted, or till it is tial reduced nearly to the confiftence of a fyrup; after Salts, which it is removed into a cellar, and buffered to 8—v—J ftand till the Salt has cryftallized. Some continue the infpiffation further, put the matter into flat earthen difhes, and pour fome Oil on the furface. Others expedite the cryftallization, by betting the liquor, duly depurated and evoporated, not in a cold cellar, but in a warm room, where it is left to fhoot in the lame manner as Sugar Candy. The cryftals are to be nimbly rinfed with water, and dried upon bpongy paper in a gentle warmth. Several of the cryftals generally prove brownifh coloured and foul: if re¬ quired to be pure and white, they are diffolved in water, the folution filtered, and bet to fhoot a becond time. The baline matter remaining after the cryftal- lization may be diluted with the water in which the cryftals were wafhed, and after due purification, fet to cryftallize again as at firft. This tedious procebs is rarely performed *, and the nature of the Salts, obtainable by it from different vegetables, has been little examined. The Salts of acid plants are fimilar in moft refpedls to Tartar, though not as fome have buppobed, perfectly the fame: the Salt of Sorrel is manifeftly more acid, and diffolves in half the quantity of water that Tartar requires. With regard to the preparation of them, much depends upon the liquor being duly purified from the grobs oily matter, which impedes the repa¬ ration and concretion of the Salt. The fweet effen- tiai Salt of the Sugar Cane cannot be procured in its concrete baline ftate, without the addition of Lime- water during the infpiffation, to promote its reparation from the unduous matter (s). (s) Fjfential Salts.'] St:hi obferves that the tedicwfnefs of the cry¬ ftallization is in great meafure owing to the vifcid oily matter of the juice, which entangles and prevents the coalefcence ot the faline particles : hence he endeavours to improve the procefs, by firft extiaft- ing; the oily and refinous matter, by Spirit ot Wine, and afterwards he by water. He directs Wormwood, Brook-lime, Pellitory, Herb-