SYNOVIA, the name given to a liquid secreted within the capsular ligaments of the joints, to facilitate motion by lubri cating these parts. The synovia of the ox is a viscid, semi-transparent fluid, of a greenish white colour, which soon ac quires the consistence of jelly, and not long after becomes again fluid, depositing a filamentous matter. Synovia mixes with water, and renders it viscid. When this mixture is boiled, it becomes milky, and some pellicles are deposited on the sides of the vessel. Alcohol produces a precipitate when added to synovia. This precipitate is albumen. After this matter is separated, the liquid still remains viscid; but if acetic acid be added, the viscidity disappears, and it becomes transparent, depositing a white filamentous substance, which resembles vegetable gluten. It is soluble in cold water, and in concentrated acids and pure alkalies. This fibrous matter is precipitated by acids and alco hol in flakes. The concentrated mineral acids produce a flaky precipitate, which is soon redissolved; but the viscidity of the liquid is not destroyed till they are so much diluted with water, that the acid taste is only perceptible. When synovia
is exposed to dry air, it evaporates, and cubic crystals remain in the residuum, with a white saline efflorescence. The first are muriate of soda, and the latter carbonate of soda. This substance soon becomes putrid, giving out ammonia during its decomposition. By distillation in a retort, it yields water, which soon becomes putrid ; water containing a por tion of ammonia, and an empyreumatic oil, with carbonate of ammonia : by wash ing the residuum, muriate and carbonate of soda may be obtained. A small portion of phosphate of lime is found in the coaly matter. The constituent parts of synovia are the following : Fibrous matter 11 8 Albumen 4 5 Mariate of soda 17 Soda 0 7 Phosphate of lime . . . . 0.7 Water 80 6 100.0