An acid obtained from the above-mentioned salt tartar by Scheele. In a solution of the super-tartrate in boiling water, he saturated the superfluous acid by the addition of chalk, as long as effervescence ensued; and expelled the acid from the precipitated tartrate of lime, by means of the sulphuric. Or four parts of tartar may be boiled in 20 or 24 parts of water, and one part of sulphuric acid added gradually. By continuing the boiling, the sulphate of potash will fall down. When the liquor is reduced one-half, it is to be filtered; and if any move sulphate be deposited by continuing the boiling, the filtering must be repeated. When no more is thrown down, the liquor is to be evaporated to the consistence of a syrup; and thus crystals of tartaric acid, equal to half the weight of the tartar employed, will be obtained. - Ure.