HYDEBABAD 94 HYDRATE Till the middle of the 17th century there was a part of it which contained deer. HYDERABAD, preferably HAIDAR- ABAD (hl-diir-a-bad'), a state of Hin- dustan, which comprehends the greater part of that central plateau of Southern jndia known as the Deccan, and is in pos- session of a Mohammedan prince, the Nizam; area, 80,000 square miles, exclu- sive of the Berar or Haidarabad As- signed Districts under British adminis- tration. The chief products are rice, wheat, maize, sugar-cane, tobacco, cot- ton, indigo, fruits, and timber. Pop. about 15,000,000. The ruler of Haidar- abad belongs to a dynasty founded by Asaf Jah, a distinguished soldier, whom the Emperor Aurungzeb made viceroy of the Deccan in 1713, with the title of Nizam or Regulator. Haidarabad, the capital, is on the Musi river, at an eleva- tion of 1,672 feet above the sea. It is surrounded by a stone wall flanked with bastions. Among the chief buildings are the extensive palace of the Nizam, the British residency, the Char Minar, or Four Minarets, built about 1590 as a Mohammedan college, the Jama Masjid, or cathedral mosque, designed after the one at Mecca. There are manufactures of silks, trinkets, and turbans. Pop. of city, with suburbs, about 550,000. Also a city, capital Sindh, B. I., pop. about 75,000. HYDER ALI (hi-der-al-'e) , an Indian prince of Arabian origin, born in Mysore in 1718. He took the field with his brother, who was in alliance with France, 1751, and in the interval between that period and 1780 acquired for him- self an independent sovereignty, and nearly brought the English presidency of Madras to ruin. His death occurred at a critical period in 1782, and he was succeeded by his son, Tippoo-Sahib, who was driven from the Carnatic in 1783. HYDNORA (hid-no'ra), a genus of pa asitic plants belonging to the order Cytinacex, which consists entirely of root-parasites. Hydnora africana is a South African species parasitic on the roots of fleshy euphorbisb and other suc- culent plants; it has a putrid smell, but is roasted and eaten by the natives, and is also used for tanning. HYDRA, or IDRA, an island of the Grecian archipelago, on the E. coast of che Morea, between the gulfs of Nauplia and ^gina; area, 20 square miles. Pop. about 6,500. HYDRA (hi'dra), in classical mythol- ogy, a monster which infested the Lake Lerna in Peloponnesus. It was the off- spi'ing of Ichidna's union with Typhon. It had 100 heads, and as soon as one was cut off', two grew up if the wound was not stopped by fire. It was one of the labors of Hercules to destroy this mon- ster; this he effected with the assistance of lolaus, who applied a red-hot iron to the wound as soon as one head was cut off. The conqueror dipped his arrows in the gall of the hydra, and all the wounds which he gave proved incurable. In astronomy, the hydra or w^ater- snake, one of the 15 ancient southern constellations. It is so long that it has been divided into four parts; (1) Hydra — i.e., Hydra proper; (2) Hydra et Crater; (3) Hydra et Corvus; and (4) Hydraa continuatio. Hydra proper is a little S. of the bright star, Regulus, which is in Leo. In zoology the typical genus of the family Hydridse. The animal is locomo- tive, single, naked, gelatinous, sub-cyl- indrical, but very contractile and vari- able in form; the mouth surrounded by a single row of filiform tentacles. Prop- agation by the formation of gemmae and ova upon or within the substance of the animal's body. If cut into pieces each will b-^-^ome a new hydra. If turned inside out the exterior surface will digest good and the interior one re- spire. Hydra was first described by Trembley in 1774. The genus contains the fresh water polypes. Hydra viridis has 6 to 10 tentacles, shorter than the body; it is leaf-green, and is found in ponds and still waters adhering to the roots of duckweed. H. vulgaris has 7 to 12 tentacles, at least as long as the body; it is orange, bi'own, yellow, or red. H. attenuata and H. fusca are rare, HYDRANGEA (hi-dran'jea), a genus of shrubs or herbs of the order Saxifra- gacese, containing about 33 species, na- tives of Asia and America. The garden hydrangea {H. hortensis) is a native of China, and was introduced into Great Britain by Banks in 1790. It is a fa- vorite for the beauty and size of its flowers. HYDRARTHRUS (hi-drar'thrus), a white swelling. The joints most sub> ject to this disease are the knee, ankle, elbow, and wrist. It can be distin- guished from rheumatic swelling of the joints by its fixed and wearing pain, which often exists for a long time be- fore any enlargement of the part is per- ceptible. HYDRATE. In chemistry, in com- bination with certain metallic oxides, water seems to play the part of an acid, forming a compound that may be con-
