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This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1821 Excerpt:...of principles, at the temperature of any experiment, has likewise tended to mislead chemists, who have deduced consequences from the first effects of their experiments. It is evident, that many separations may ensue without precipitation; because this circumstance does not take place unless the separated principle be insoluble, or nearly so. The soda cannot be precipitated from a solution of sulphate of soda, by the addition of potash, because of its great solubility; but, on the contrary, the new compound itself, or sulphate of potash, which is much less soluble, may fall down, if there be not enough water present to suspend it. No certain knowledge an therefore be derived from the appearance or the want of precipitation, unless the products be carefully examined. In some instances all the products remain suspended, and in others they all fall down. as may be instanced in the decomposition of sulphate of iron by lime. Here the acid unites with the lime, and forms sulphate of lime, which is scarcely at all soluble; and the still less soluble oxide of iron, which was disengaged, falls down along with it. Many instances present themselves, in which decomposition does not take place, but a sort of equilibrium of affinity is perceived. Thus, soda, added to the supertartrate of potash, forms a triple salt by eombining with its excess of acid. So likewise ammonia combines with a portion of the acid of muriate of mercury, and forms the triple compound formerly distinguished by the barbarous name of sal alembroth. When we reflect maturely upon all the circumstances enumerated, or slightly touched upon, in the foregoing pages. we may form some idea of the extensive field of research, which yet remains to be ex plored by chemists. If it were possible to procure simpl...