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Germ Theory of Disease

the theory that certain diseases are communicated from an infected person to an uninfected one by living organisms which gain access to the body of the afflicted person by the air or food, or drink, and which, growing and multiplying in the body they invade, produce the changes characteristic of the particular disease.

The period during which the living particles of contagious matter retain their vitality, like the rate of their growth and multiplication, varies in different cases, but it is limited in all. Few, if any, resist the destructive influence of a temperature of 300° F., while most succumb at the temperature particularly if exposed for some time.

Animal poisons generally are destroyed by boiling, and clothes, sheets, etc., infected, may be rendered pure by being exposed to a temperature of 300° F.

These living organisms are grouped together as microbes or micro-organisms, and are divided into different classes.

The micrococcus is a round form about the 32,000th of an inch in size, and multiplies by fission. The bacterium is rodshaped, about the 10,000th of an inch long, with rounded ends; it also multiplies by fission. The bacillus is a third form also rod-shaped, and somewhat larger than the bacterium. They often form long chains or threads, and increase by division and by spore formation. Vibrio and spirillum are somewhat similar forms; and, like the others, increase with the temperature of 200° or even less, GERM THEORY a rapidity beyond conception. The connection 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 posed 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- GEROULD they have one origin and one only, and that is a preceding case of disease. The "germ theory" affords the hope and suggestion of a method of diminishing, if not of getting rid of, such diseases altogether, and to some extent also indicates the direction in which their cure is to be sought.

Paul Delaroche at Paris, at the same vated in one flask after another through Augustus and the Birth of Christ," was successive generations, only a single minute drop of the material in one flask being used to inoculate a succeeding In this way a pure cultivation is obtained, a cultivation, that is, contain one. the particular microbe and none other. If this is the true cause of the disease, then a drop of the solution conit introduced into the body of an animal capable of the disease ought to produce it, and the particular organism introduced should be found multiplying in the blood and tissues of the infected animal. Such a demonstration has been GÉRÔME, LÉON (zhā-rōm'), a French painter; born in Vesoul, France, May 11, 1824; and in 1841 entered the studio of 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 exhibited in 1855; and four years later his "Roman Gladiators in the Amphitheater" 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 Molière," "The Prisoner," "Cleopatra and Plague at Marseilles," "Death of St.

Jerome," "Lioness Meeting a Jaguar," and "The Gray Heights" (1874), are among the best known of his subsequent Cæsar," "The Death of Cæsar," "The works. He died at Paris, Jan. 10, 1904.

GERONA (hā-rō'nä), a city and capital 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, corkcutting, 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 French.

Pop. (1918) of province 330,153; of city, about 16,000. 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 investigations 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- GERONTES (ge-ron'tēz), a number of sumptive patients, and multiply also by magistrates of Sparta who, with the spores. After the epidemic of cholera ephors and kings, had the supreme power in Egypt in 1883, which spread to France in the State. They were not eligible and Italy, investigations were under- to office before they had attained the taken by French, German, and British age of 60 years. Their number is variously stated at 20 and 32. 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