VISAYAS 234 VISCONTI each specific disease breeds true, though, in the course of 1,000 years, it is possible that the changes within certain limits may take place, as is the case in animals and plants. The natural conclusion follows that diseases of this class do not originate spontaneously, but are propa- gated each from its own kind, though some contend that they do not originate, even in our own day, spontaneously or autochthonously. Another remarkable peculiarity belonging to many, but not to all, diseases propagated by a specific virus, is that a single attack of the dis- ease successfully surmounted produces absolute or relative immunity for a cer- tain length of time, or even for the re- mainder of life. See Bacteria. VISAYAS, THE, a group of islands which occupy the central part of the Philippine Archipelago, between Luzon on the N., Mindanao on the S., the Pacific Ocean on the E., and Paragua on the W. They lie between lat. 9° 2' and 12° 39' N., and between Ion. 121° 48' and 125° 50' W.; area, 57,714 square kilometers; pop. about 3,500,000. The group may be divided into three parts, each including several adjacent islands. The principal islands of the first group are Romblon and Panay, of the second, Negros, Cebu, and Bohol, and of the third Samar and Leyte. Many of the islands are moun- tainous, but there are valleys and plains which are usually very fertile. Agri- culture is quite extensively carried on. There are large crops of rice, sugar cane, subacao, coffee, chocolate, wheat, corn, tobacco, hemp, etc. The forests of the islands are generally rich in excellent building and cabinet woods, such as molave, ipil, banaba, durigon, alintatao, narra, etc. There is also found in the forests an abundance of pitch, resin, gum, mastic wax, and honey. Gold, silver, lead, coal, marble, etc., are mined to a greater or less extent in some of the islands. Manufacturing is carried on to a considerable extent. In the province of Antique, on the island of Panay, the manufacture of fabrics from pineapple fiber, jusi, and sinamay is flourishing. Hunting and fishing are also important industries. VISCERA, in anatomy, the contents of the great cavities of the body, as of the skull, chest, and abdomen, but in popular language restricted to the organs of the thorax and abdomen ; the bowels ; the en- trails. VISCHER, PETER, a German sculp- tor; born in Nuremberg, Bavaria, in 1455, son of a worker in bronze. He attained great fame as an artist and received orders both from German and foreign prmces. His most celebrated work is the tomb of St. Sebaldus in Nuremberg, which contains 72 figures, besides those of the apostles and prophets. He died in Nuremberg, Jan. 7, 1529. VISCIN, a waxy substance, the princi- pal constituent of bird-lime, extracted from the stalks, leaves, and berries of the mistletoe. It is clear, colorless, in- odorous, and tasteless, insoluble in water, but slightly soluble in alcohol, has the consistency of honey at ordinary temper- atures, but becomes more fluid at 30°. Heated to 100°, it is as fluid as almond oil. VISCONTI, the name of one of the most illustrious families of Lombardy, which rose to the sovereign rank in northern Italy in the 13th century, and was equally distinguished by the share it took in the political contests of the Middle Ages, and by the services which it rendered to literature and science. The name Visconti is derived from the Latin vice-comites, and at first was merely the title of an office, but it gradually became GIOVANNI VISCONTI a family surname, though when it came to be applied to this family authentic history fails to explain. The power of Visconti began in 1277, when Ottone Vis- conti, archbishop of Milan, vanquished his popular opponents headed by Mar- tino della Torre, and became perpetual Lord of Milan. Two of the most im- portant members of the family^ were Matteo, who was compelled to resign by Pope John XXII.; and Giovanni Gale- azzo, who brought the newer and gran- deur of Visconti to its highest point. He founded the library at Paris; the Cathe- dral of Milan, etc.; anQ conquered Padua, Verona, Vicenza, etc. In 1441, Filippo-Maria Visconti engaged the serv-
