GERM THEORY 304 GEROULD a rapidity beyond conception. The con- nection between these micro-organisms and the various forms of zymotic disease has been thoroughly established. The only method of investigation that yields reliable results is to separate the organisms supposed to be the cause of the disease, and cultivate it outside of the body. Thus a drop of blood from a person suffering from a special disease, which contains the bacteria, or bacilli, etc., believed to be the producers of the disease, is placed in a flask containing a nourishing material, care having been taken to destroy all other organisms in the flask. The special microbe flourishes there, let us suppose. It is then culti- vated in one flask after another through successive generations, only a single minute drop of the material in one flask being used to inoculate a succeeding one. In this way a pure cultivation is obtained, a cultivation, that is, contain- ing the particular microbe and none other. If this is the true cause of the disease, then a drop of the solution con- taining it introduced into the body of an animal capable of the disease ought to produc(' it, and the particular organism introduced should be found multiplying in the blood and tissues of the infected animal. Such a demonstration has been given of the cause of a few diseases. Dr. Koch, of Berlin, published in 1876 a paper giving a full account of the life history of the bacillus organism which had been observed in animals dead of splenic fever; and in 1877 the great French chemist, Pasteur, proceeded to investigate the subject, and his investi- gations conclusively support the germ theory of disease. In 1882, Dr. Koch, of Berlin, announced the discovery of a micro-organism in tuberculosis, a disease believed to be the chief, if not the only, cause of consumption of the lungs. These microbes are found not only in the lungs of persons who have died of tubercle, but also in the spit of tubercular and con- sumptive patients, and multiply also by spores. After the epidemic of cholera in Egypt in 1883, which spread to France and Italy, investigations were under- taken by French, German, and British commissioners. All investigation, however, seems to point to the fact that every infectious or contagious disease is due to some form of micro-organism, and that there is one particular organism for each particular disease. Each organism produces its own disease and none other; and the special disease cannot arise unless its germ has gained entrance to the body. The channels through which these germs obtain entrance are innumerable, but they have one origin and one only, and that is a preceding case of disease. The "germ theory" affords the hope and sug- gestion of a method of diminishing, if not of getting rid of, such diseases alto- gether, and to some extent also indicates the direction in which their cure is to be sought. GEROME, LEON (zha-rom'), a French painter; born in Vesoul, France, May 11, 1824; and in 1841 entered the studio of Paul Delaroche at Paris, at the same time attending the School of Fine Arts. In 1863 he was appointed Professor of Painting in the School of the Fine Arts. His first great picture, "The Age of Augustus and the Birth of Christ," was exhibited in 1855; and four years later his "Roman Gladiators in the Amphi- theater" gained him great reputation, that was still further enhanced by "Phryne Before Her Judges" (1861). In the same year he exhibited, "Socrates Searching for Alcibiades at the House of Aspasia," "The Two Augurs," and a portrait of "Rachel." "Louis XIV. and Moliere," "The Prisoner," "Cleopatra and Caesar," "The Death of Csesar," "The Plague at Marseilles," "Death of St. Jerome," "Lioness Meeting a Jaguar," and "The Gray Heights" (1874), are among the best known of his subsequent works. He died at Paris, Jan. 10, 1904. GERONA (ha-ro'na), a city and capi- tal of the province of Gerona, Spain; 65 miles N. E. of Barcelona. It contains a beautiful Gothic cathedral of the 14th and 15th centuries. The inhabitants carry on the manufacture of paper, cork- cutting, spinning, and weaving. The town was formerly a place of great strength, and has undergone several notable sieges, particularly in 1653, 1684, 1694, 1706, and 1809, on each occasion by the Fi*ench. Pop. (1918) of province 330,153; of city, about 16,000. GERONTES (ge-ron'tez), a number of magistrates of Sparta who, with the ephors and kings, had the supreme power in the State. They were not eligible to office before they had attained tbe age of 60 years. Their number is vari- ously stated at 20 and 32. GEROULD, KATHARINE FULLER- TON, an American writer, born in Brock- ton, Mass., in 1879. She graduated from Radcliff e College in 1900. She was on the faculty of Bryn Mawr from 1901 to 1910. Her published writings include "Vain Oblations" (1914); "The Great Tradi- tion" (1915); "Modes and Morals" (es- says) (1919). She was a frequent con- tributor of stories, essays, and verse to magazines.