Page:The New International Encyclopædia 1st ed. v. 19.djvu/69

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TARTARIC ACID. 49 TARTE. lizes with half a molecule of water. Acid potas- sium tartrate, or bitartrate of potash, KHC.H.Oj, is prepared from argol by extraction with boiling water and filtering tlie solution thus obtained through charcoal. The salt crystallizes readily as the hot solution cools. The snowy white rhombic prisms which are thus deposited constitute cream of tartar, which is moderately soluble in cold water and but sparingly soluble in alcohol. It is an excellent saline purgative anil diuretic and is therefore largely used in medicine. Calcium tartrate, CaC,H,Oa + 4H2O, is practically insoluble in cold water and but sparingly soluble in hot water. The insolubility of the acid tartrate of potassium and of the tar- trate of calcium often helps to identify tartaric acid. Tartar emetic is described in a special article. Tartaric acid has been known since the earliest times, in the form of tartar; Scheele was the first to obtain the acid in the free state and to determine its principal properties (1709). Like any other acid, tartaric acid promotes the secretion of saliva, and may therefore be used to allay thirst. When taken internally it is de- composed in the blood with formation of alkaline carbonates, which cause an increase of the alka- linity of urine. A remarkable modification of tartaric acid is known as racemic or paratartaric acid, C.H.Oj + 2HjO. It is a frequent associate of tartaric acid, but is especially abundant in the grapes of the Vosges district. While in most respects it ex- hibits a close resemblance to tartaric acid, it crystallizes more readily from solution ; contains two equivalents of water of crystallization; is less soluble in alcohol ; and the racemate of lime is soluble in hydrochloric acid, and is precipitat- ed unchanged on adding ammonia. Its most important diflference. however, is that its solu- tion does not rotate the plane of polarized light, while a solution of ordinary tartaric acid exerts a well-marked right-handed rotation. Pasteur proved that racemic acid is a mixture of ordinary tartaric acid (to which, from its optical prop- erty, he applies the term dextro-raccmic acid) and of an acid which produces left-lianded rota- tion, to which he gives the name Iwro-racemic acid. (These acids are also known as dextro- tartaric and Uvro-tartaric acids). He found that, by saturating racemic acid with soda and ammonia, and allowing this solution to crystal- lize slowly, two varieties of crystals are obtained, which may be distinguished by their form, in the same way as the image and the reflection of the inuige in a mirror diflfcr, or as right-handed and left-handed. If the two kinds of crystals are separated, and then dissolved, each solution is found to act powerfully on polarized light, but in opposite directions. On separating these acids from their bases, and mixing equal parts of concentrated solutions of each, racemic acid is again formed, w-hich exerts no action on a polar- ized ray. Besides the three modifications mentioned above, viz.. ordinary or dextro-tartaric acid, hrvo-tartaric acid, and racemic acid, a fourth modification of the same chemical composition and constitution, known as mcso-tartaric, anti- tartaric, or inactive tartaric acid, has been ob- tained. It may be prepared by heating, in a sealed glass tube, 30 grams of ordinarj' tartaric acid with 3 or 4 cubic centimeters of water, at 105° C, for about 48 hours. In the anhydrous state it melts at about 140° C. ; usually, how- ever, it is obtained in the form of crystals having the composition CJloO, + HjO. It is very soluble in water. Its acid potassium salt, too, is very soluble in water, and its calcium salt crystallizes with 3 molecules of water: CaCjH.O, -f 3H.0. The dill'erent modifications of tartaric acid have also been prepared synthetically. Their relation to one another has been explained stereo-chemically. See Stekeo-Chemistry. TARTARIN, tAr'ta'raN'. The hero of three tales by Alphonse Daudet, Tartarin of Tarascon (1872), Tartarin on the Alps (1885), and Port- Tarascon (1890). The boastful, expansive, childlike Tartarin personifies the Gascon type, with which Daudet was intimately familiar. TARTARS. See Tatars. TAR'TARUS (Lat., from Gk. Tdprapos). According to Homer, a deep and sunless abyss, as far below Hades as earth is below heaven, and closed in by iron gates. Into Tartarus Zeus hurled those who rebelled against his authority, e.g. Cronos and the Titans. It is to be noted that such typical sinners as Tityos, who offered violence to Leto, and after his death by the arrows of Apollo and Artemis was con- demned to have his liver perpetually eat- en by vultures, or Sisyphus (q.v. ), Tantalus (q.v.), and Ixion (q.v.) are represented in the earlier poems as suffering in sight of the other shades. In the later conception, when the idea of a judgment in the other world and a separa- tion between the good and bad had become well developed, Tartarus became the place of punish- ment for all sinners. TAR'TARY (properly Tatary) . The name which, in the Middle Ages, was applied to the central part of Eurasia. In later times a dis- tinction was made between European and Asiatic Tartary, the former comprising that part of Russia which was once the Khanate of the Crimea. The term Asiatic Tartary, first applied to the whole of Central Asia, has gradually been confined to the independent portion of Turkestan. TARTE, tiirt, Jo.seph Israel (1848—). A Canadian statesman. He was born in the Prov- ince of Quebec, was educated at L'Assomption College, and was admitted to the bar in 1871. Afterwards he became editor of Le Cana- dien and then of L'Eve'nement, in Quebec. Po- litically he was a Conservative until 1891, but after that date he supported the Liberals. He was a member of the Legislative Assembly of Quebec in 1877-81, and became one of the active political organizers of his party in that, province. As the avow'ed foe of jobberj' and corruption in every form, he had already given dissatisfaction by his criticism of certain politicians and measures; but after his election to the Dominion House of Commons in 1891. as an Independent Conserva- tive, he vigorously attacked the administration of Sir .John A. Macdonald, his political chief, alleging corrupt practices by Ministers. This compelled him to sever his connection with the Conservative Party, and when the Laurier ad- ministration came into power in 1896 he was ap- pointed Minister of Public Works. He held that position until 1902.