CREAM OF TARTAR CREBILLON 469 collects in a crystalline deposit upon the bot- tom and sides of wine casks during the fermen- tation of the wine. Its chemical composition is : tartaric acid 2 equivalents, = 132 ; potassa 1, = 47'2 ; and water 1, = 9. As the saccha- rine matters which hold the tartar in solution are converted into alcohol, the salt is precipi- tated in a crude state, together with some tar- trate of lime and the coloring matter of the wine. Red wines give a red color to the crude article. When the crude salt is dissolved in boiling water, and this is allowed to cool, crystals of the cream of tartar are deposited and form a crust on the bottom of the vessel, cold water holding in solution only T |j of its weight of the salt, and boiling water ^-. The crust is redissolved in boiling water, and 4 or 5 per cent, of pipe clay is added. On evapo- rating the solution, the clay precipitates with the coloring matter, and the salt of tartar is deposited in white crystals. These are bleached by being spread upon cloths for some days and dried, and then constitute the cream of tartar of commerce. It is usually sold as a powder, and in this state is liable to have been mixed with various adulterants, as chalk, clay, gypsum, sand, flour, &c. It is therefore better to purchase it in the crystalline form in which it is received from the French manufacturers. It is, however, never pure, always containing a small percentage of tartrate of lime. Cream of tartar is used in medicine as a diuretic, re- frigerant laxative, and cathartic. In the dose of 40 grs. or less, largely diluted with water, and repeated several times a day, it is a diuretic and moderate refrigerant. In the dose of about two drachms it is a laxative, and in the dose of half an ounce it acts as a cathartic, produ- cing watery discharges. Combined with digi- talis and squill, it is often advantageously pre- scribed in dropsical affections. It is used as a refrigerant drink in many febrile conditions. Its laxative action is useful in piles and pro- lapsus ani. As a purge (generally combined with jalap) it often does good service in in- flammation, and especially in inflammatory dropsy. Its tendency is to render the urine alkaline, though it is less powerful in this di- rection than the more soluble salts of the al- kalies combined with vegetable acids. A re- freshing beverage called imperial is prepared by dissolving half an ounce in three pints of boiling water, and adding four ounces of white sugar and half an ounce of fresh lemon peel. Cream of tartar and tartrate of antimony com- pose the medicine tartar emetic. Rochelle salt is prepared by adding cream of tartar to car- bonate of soda, by which a tartrate of potassa and soda is produced. When decomposed by heat, cream of tartar is converted into a pure carbonate of potassa. Mixed with half its weight of nitrate of potash and deflagrated, it forms the flux called black flux, used for cru- cible assays. White flux is prepared with two parts of nitre to one of cream of tartar. In making bread, cream of tartar is often usefully employed, mixed with half its weight of car- bonate of soda. The excess of acid produces slow effervescence, and the escape of carbonic acid gas, distending the dough, causes it to rise. CREATIVE (Gr. Kptas, flesh), a neutral crys- tallizable substance, one of the normal ingre- dients of the urine of man and animals ; so called because it is derived from the muscular flesh, in which also it exists in appreciable quantity. Creatine is composed of oxygen, hydrogen, carbon, and nitrogen. It crystal- lizes in rectangular prisms. It is soluble in water, slightly soluble in alcohol, but not at all in ether. It exists in the urine, in the hu- man species, in the average proportion of about 1-25 part in 1,000, and in the muscles in the proportion of 0'67 part in 1,000. It is re- garded as one of the products of the physio- logical disintegration or waste of the muscular tissue, from which it is absorbed by the blood, ^carried by the circulation to the kidneys, and 'thence eliminated from the body as an ingre- dient of the urine. CREBILLON. I. Prosper Jolyot de, a French tragic poet, born at Dijon early in 1674, died in Paris, June 17, 1762. His father placed him in the office of an attorney who was fond of the drama and encouraged his clerk to de- vote himself to dramatic literature. His first tragedy, Idomenee, was performed in 1705. Atree, in 1707, produced an impression by its gloomy plot and energetic style. Mectre suc- ceeded in 1709 ; and two years later Rhada- miste et Zenobie, which is still considered his best production. His next tragedy, Xerx&s, was a failure ; and Semiramis, performed in 1717, and Pyrrhus, in 1726, were little more success- ful. He now kept aloof from the stage for 22 years. Having squandered his large earnings and lost his father and his wife, he retired to a miserable garret, where his sole companions were dogs, cats, and ravens, and where he lived neglected by all his friends, except his son. In 1731 the French academy elected him one of their number ; and he wrote a poem as his reception discourse. Some 14 years later Mme. de Pompadour, who was dis- satisfied with Voltaire, thought of bringing Crebillon into competition with him. The old dramatist received a pension of 1,000 livres, and was encouraged to resume his former call- ing. He now completed his tragedy of Cati- lina, which was performed Dec. 12, 1748, in a style of unusual splendor, at the king's ex- pense, and warmly applauded by the court party, while his superiority over Voltaire as a tragic poet was loudly proclaimed. His last effort was his Triummrat, which he wrote when over 81. Among French tragic poets Crebillon ranks next to Corneille, Racine, and Voltaire. II. Claude Prosper Jolyot de, a French novelist, son of the preceding, born in Paris, Feb. 14, 1707, died there, April 12, 1777. He was a gay companion, full of wit and humor, and he wrote a series of licentious novels which pleased Miss Stafford, a young, handsome, and
